Rabu, 30 November 2011

What Causes Engine Compression Loss?

What Causes Engine Compression Loss?

Engine compression is measured in the cylinder, where the air/fuel mixture enters and is then ignited. The burning, expanding gases push the piston, translating that energy into forward movement. The ability to confine this explosion in the cylinder is measured and called compression. Any leak out of the cylinder is defined as compression loss, which can severely lower the power output of the engine.

Bad Valves

    In a car engine, the intake and exhaust valves are typically located on top of the cylinder. The intake valve opens and lets fuel and air into the cylinder for combustion. After combustion, the exhaust valve opens to expel the exhaust gases.

    Bad valves are caused mainly by overheating. Overheating can heat the valves' stems to the point of warping. The warped valve stems do not allow the valves to seat properly, allowing gases to leak out. This results in compression loss.

    The exhaust valve fails most often because it is exposed to the hot exhaust gases, which reach up to 1,200 to 1,350 degrees. The heated valve breaks or warps, causing leaks in the cylinder and compression loss.

    Valves can also acquire carbon buildup. Carbon buildup usually occurs on the exhaust valve due to the continuous passing of burnt gases. These burnt gases foul the valve seat, preventing a good seal on the exhaust valve. Gases then escape, which in turn causes compression loss.

Piston Holes

    Pistons are housed in the cylinder. When combustion occurs, hot gases push the piston, which in turn operates a crank shaft. Piston holes lead to leakage and low compression. Overheating is one cause of piston holes. When overheating occurs, hot spots form. These hot spots eventually wear holes in the pistons. Piston leaks result in low compression because the gases do not build up in the combustion chamber. Bad spark plugs, inferior gas with low octane and defective fuel injectors can all trigger hot spots on the pistons and eventually lead to holes.

Leak in Cylinder Head

    The cylinder head is located at the top of the engine block. It enables combustion by allowing fuel and air to pass into the cylinder and then escape after the mixture is burned. The cylinder head is bolted to the engine block with a gasket in between. If the gasket breaks down, a small hole develops between the cylinder head and the cylinder. This is known as head gasket failure. The leak in the gasket allows gases to escape and leads to compression loss and poor engine performance. The most common cause of head gasket failure is overheating. Extreme overheating leads to warping of the head or engine block, which then results in a breakdown of the gasket seal.

Minggu, 27 November 2011

GM Ignition Control Module Troubleshooting

GM Ignition Control Module Troubleshooting

The most important part of a vehicle's ignition system, including a GM vehicle, is the ignition control module because it regulates all aspects of the ignition, including the spark plugs. Mechanics use a special diagnostic scope to identify any existing problems within the ignition system, but if you do not have a scope, there are ways to visibly troubleshoot components of a GM vehicle's ignition system.

No Lubrication

    Grease or silicone should always be present on modules that are in good working condition to prevent the penetration of heat through the module's surface. Inspect the module for a visible layer of grease or silicone on the back of it. If this film is absent, the module needs to be replaced.

Irregular Spark

    Install a timing light and monitor the engine for an irregular spark while the light is operating. If you notice an abnormal spark, but the spark plugs do not look damaged, the ignition module may be faulty.

Cracks

    Any cracks or damage to the module's surface indicate a problem. Remove the module and inspect it for damage or cracks on the surface or around the mounting screws. If there is any visible damage, replace the module.

My Town & Country Won't Start After I Replaced the Battery

A Town and Country vehicle may continue to have starting troubles after the battery is replaced. There is no quick answer as to why this happens as there may plenty of reasons why the Town and Country will not start.

Wrong Battery

    If the wrong battery has been put into the Town and Country, it may not start. A replacement battery must have the same cold cranking and cranking amp values as the battery it just replaced. If the new battery has lower amps, it will pose a power problem.

Cables

    If the battery's positive and negative cables are not attached to the battery's terminals, then the Town and Country will have starting problems. The starting problems will remain if the cables are loosely attached. Also, check to see if the cables are wet or damaged. The cables may need to be replaced.

A Dud

    The replacement battery may not have a charge. Check the date code sticker on the battery and see how recently it was manufactured. Battery date codes use an A through L letter for the month, and a two digit number for the year. For example, A11 stands for January 2011, while L09 means December 2009.

Sabtu, 26 November 2011

Signs of a Bad Power Steering Pump

Signs of a Bad Power Steering Pump

Power steering makes a driver's job a lot easier and today nearly all vehicles have this feature. The system uses power from the engine to operate a small hydraulic pump, which in turn provides assistance to the driver when the steering wheel is turned in one direction or the other. Like all mechanical components, however, the pump can develop problems. By learning to recognize the signs of a bad power steering pump drivers can identify and fix problems before they become serious.

Difficulty Steering

    When problems develop in the power steering pump, the pump will usually not deliver the pressure required to assist the driver in turning the steering wheel. The driver will notice a marked increase in the effort needed to turn the wheel.

Noise

    Most steering pump problems will be accompanied by loud noise. Depending on the nature of the problem, the noise might be a loud clicking or rattling, caused by a broken or defective pump vane. Or it might be a loud whine or moan, possibly indicating problems with a pump bearing or the input shaft. A loud growling noise can indicate a blockage inside the pump and a continuous loud swishing is often caused by a low power steering fluid level. Any unusual noise is the sign of a problem that should be addressed as soon as possible. Be sure to open the vehicle hood and verify that the noise is coming from the power steering pump and not another engine component.

Steering Wheel Does Not Return to Center

    If the steering wheel does not easily return to the center position after turning the vehicle it can signify problems with the power steering pump. The likely culprit is a problem with the input shaft bearing.

Fluid Leaks

    If there is fluid leaking out of the power steering pump then a seal or gasket has failed or the pump casing has cracked. Be sure the fluid is not simply a result of an overflow from the fluid reservoir caused by overfilling.

Jumat, 25 November 2011

Problems With the ABS on a 1999 Dodge Durango

Problems With the ABS on a 1999 Dodge Durango

The 1999 Dodge Durango anti-lock braking system (ABS) helps the driver control the vehicle by preventing skidding when the brakes are applied. There have been five recalls on the 1999 Durango, but none of these recalls concern the ABS brakes. According to Car Complaints, some Dodge Durango owners have had various complaints about the ABS brakes, however.

ABS Warning Light

    Some 1999 Dodge Durango owners have complained that the ABS warning light comes on and remains on even after repairs. This problem has been attributed to a defective ABS control module, according to Car Complaints. The ABS light is designed to come on when there is a brake problem, but when owners have taken the vehicle to the dealership, mechanics have found no problems with the brake pads, calipers or rotors. If the control module is the problem, then this component needs to be replaced. Otherwise, the warning light cannot warn the vehicle owner when a problem with the brakes does occur.

Caliper Pins

    The calipers on the ABS brakes of the 1999 Dodge Durango control the pressure applied to the brake pads when the operator pushes the brake pedal. The calipers are held together with a pin which slides through the top of the calipers. In some vehicles, this pin has slipped out, causing the calipers to become misaligned and leading to brake pad vibration. If the caliper pins slip out, the Durango needs to be taken into the dealership so this pin can be replaced with a larger diameter pin.

Brake Pads

    Some 1999 Durango owners have reported premature wear of the vehicle's brake pads. The brake pads are the components that press against the brake rotors and cause the Durango to stop. The only cure for premature pad wear is to have superior brake pads installed. Any Dodge dealership or independent mechanic can perform this task.

How to Work My OBD-11 AutoScanner

On-Board Diagnostics Version II (OBD-II) is a standardized system to help determine common problems in a vehicle. Since 1996, vehicles produced in the United States are OBD-II compliant. The OBD-II AutoScanner is a device that you can connect to your vehicle to help diagnose what is causing problems. Once you connect this device to your vehicle, you will receive a code that you can use to determine problems with your car.

Instructions

    1

    Insert the "DTC Lookup" CD into your computer's disc drive and close it. Click on the "Install" button on the screen that appears and follow the onscreen instructions to install the software. Click "Finish" when prompted and remove the CD from the tray. Open the program that you just installed and leave it up on your computer.

    2

    Locate the "Data Link" connection for your vehicle. Every vehicle made after 1996 in the United States has one and it is typically located underneath the dashboard on the driver's side. If it is not located here, there will be a label explaining where it is located in your vehicle.

    3

    Connect the data cable from the OBD-II scanner to the "Data Link" connection. Remove the cover over the connection if one is present. When you insert the cable, you will notice that the power for the OBD-II is on. It is now ready for use.

    4

    Press the "Up" or "Down" button to highlight the "Read Codes" option on the main menu and press the "Enter" button to select. Wait a few moments as the OBD-II performs a diagnostic scan. If it detects problems, a five-digit code will appear on the screen along with a message telling you how many codes it detected.

    5

    Press the "Up" and "Down" buttons to cycle through the available codes. Go back to your computer and type in the codes one at a time in the diagnostic program to determine the meaning and cause of each code. If you are unable to find the code in the list, you can find additional codes by visiting the website or calling customer support for your vehicle's manufacturer.

How to Troubleshoot a Grand Prix ABS Light and Traction Control Light

How to Troubleshoot a Grand Prix ABS Light and Traction Control Light

The anti-lock braking system (ABS) and Traction Control systems in your Grand Prix both use the ABS wheel-speed sensors and modulator valve assembly to control wheel slip. The ABS system monitors the wheel-speed sensors and relieves brake pressure on a wheel that it senses is nearing lock-up. The Traction Control system monitors the same wheel-speed sensor and applies brake pressure to any wheel it senses over accelerating. Diagnosis of these systems is accomplished using a scan tool and the car's on-board computer diagnostics function.

Instructions

    1

    Check the tires for proper wheel size and check the fluid level in master cylinder. Improper tire size, such as two different sizes, will cause the wheels to turn at different speeds and may set a false code when the computer senses this as potential wheel lock-up. Low fluid level in the brake master cylinder will result in shutdown of the ABS and Traction Control system to prevent introduction of air into the brake system.

    2

    Turn the ignition key off and insert the scan tool's connector into the vehicle's diagnostic connector. The diagnostic connector in OBD-II equipped Grand Prix is located under the driver's side of the dash near the steering column. Turn the ignition key on and retrieve trouble codes according to the instructions supplied with the scan tool. In most cases you will select "Read Codes" from the onscreen menu or push the "Read" button on the front of the scan tool to retrieve codes. Go to step two if the code indicates a wheel speed sensor fault or step five if the codes indicates a solenoid fault.

    3

    Select "Data" from the onscreen menu and scroll through the list until wheel speed sensor data is displayed on the screen. Test drive the car while monitoring the wheel speed signals, indicated by the fault code, on the scan tool. If the wheel speed signal is different from the remaining wheel speed signals, test the resistance of the sensor.

    4

    Unplug the faulty wheel speed sensor, located on the back of the wheel bearing and hub assembly at each wheel in the Grand Prix and test the resistance of the sensor using your digital volt/ohm meter set to read resistance. The resistance of a good wheel speed sensor will be1k ohms +/- 10 percent. Replace the sensor if the meter shows 0 ohms, infinite ohms, or the resistance is not 1k ohms +/- 10 percent.

    5

    Check fuses in the fuse block under the dash and under the hood. The fuses for the ABS and Traction Control systems are marked on the body of the fuse blocks. Replace any faulty fuses before continuing with the tests. Unplug the modulator valve assembly located on the driver's side of the passenger compartment near the master cylinder and test the resistance of solenoids using you digital volt/ohm meter. Replace the modulator valve assembly if 0 ohms or infinite resistance are measured at the assembly.

Rabu, 23 November 2011

1993 Buick 3800 Engine ECM Information

The 1993 Buick uses a strong V-6 engine called the 3800, which was a reliable engine. The engine uses a Engine Control Module (ECM) to control its workings. The ECM has a reputation for failing, which causes erratic performance and difficulty starting.

Computers

    The Engine Control Module is one of the early attempts at utilizing computer technology on cars. The ECM is also called an Engine Control Unit. The ECM controls the amount of fuel that moves to the pistons and the mixture of fuel, as well as idle speed. The unit can also adjust to changing driving conditions.

The Engine

    The 3800 was the main engine used in the Buick Regal, which was the full-sized Buick in 1993. The engine is 231.4 cubic inches and produces 170 horsepower and 225 foot-pounds of torque or pulling power. The car is rated with a top speed of 131 miles per hour and completes the quarter mile in 16.5 seconds. The car has a combined highway and city mileage rating of 20.7 miles per gallon.

Problems

    The Engine Control Module on the 1993 Buick has a reputation of failing on cars such as the Buick LeSabre. The ECM controls fuel and can cause stalling of the engine and difficulty in shifting gears, causing the car to become inoperable.

Selasa, 22 November 2011

Grand Cherokee Air Conditioning Problems

The Jeep Grand Cherokee is a mid-sized all terrain vehicle that is suitable for in town driving, road trips, and off-roading adventures. Jeep has been manufacturing vehicles for 70 years. The various Jeep models are all built to embody a spirit of freedom and pride. As with any new or used vehicle, certain mechanical issues can arise. The Jeep Grand Cherokee has been known to have specific issues with the air conditioning regardless of the age of the vehicle.

Incorrect Airflow or Temperature

    The Jeep Grand Cherokee's air conditioning system can have issues such as inconsistent airflow ans fluctuations in the air temperature. Grand Cherokees have a dual climate control system that regulates the air. It is possible that one of the motors or doors within the dual climate system may have broken. A broken door within the system will not allow the temperature to be adjusted. It will also restrict the airflow, depending on the severity of the break. In either case, the issues must be fixed for the air conditioning to correctly work.

Air Conditioning Water on the Floor Board

    It is not uncommon for air conditioning water to leak onto the floor board in a Jeep Grand Cherokee. The Denlor's Tools website explains that the water could be the result of the evaporator drain becoming clogged. The drain can be cleaned with compressed air to reduce the buildup of condensation. Also, it is possible that the donut seal that fits around the air conditioning drain might have compressed too tightly, which would allow water to escape. Replacing the donut seal or drain will be required to solve the problem.

Inconsistency in the Amount of Refrigerant

    Another problem with the air conditioning in the Jeep Grand Cherokee is the inconsistency in the amount of refrigerant in the air conditioner. The system can lose its charge, which will cause the amount of refrigerant to fluctuate. Use an air conditioning gauge to check if the pressure is too low or too high. In a dual climate control air conditioner, the air will blow colder on the passenger side if the pressure is too low. The system should be recharged and filled with the correct amount of refrigerant to resolve the issue.

Car Scanning Tools

Car Scanning Tools

Most cars produced post-1996 are equipped with the OBD-II system. This stands for On-Board Diagnostics. When something is wrong with a car, it will generate an error code through the OBD-II system. These computer signals can tell the mechanic working on the car what the problem is. However, specialized equipment is required to read the error signals.

Computer to Vehicle Connections

    The first way to scan a vehicle's error codes is to use a scanner in the form of a cable that connects your vehicle to your computer. These products will come with software that you install in your computer, and should connect via a standard USB connection, such as the Autotap Express.

    Connect the cable to the diagnostic port in your vehicle. The software should then be able to display any error codes, so you can diagnose your vehicle's problem.

Standalone Scanners

    There are also hand-held scanning tools that plug into your car's computer. These come in varying degrees of complexity. Some of these tools retail for less than $100. You just plug the tool in and receive the error code, although you may then have to search the Internet to find out what the code indicates is wrong with your vehicle.

Different Scanning Codes

    Whether you are using a scan link cable or a standalone scanning unit, you need to be aware of the different types of codes that are used. Some scanners can read all of these codes, while others may only be able to read certain types. Find out what type of OBD-II codes your vehicle uses before you purchase a scanner.

Blown Headgasket Symptoms in Honda Accord

Blown Headgasket Symptoms in Honda Accord

Since its introduction in 1976 the Honda Accord has earned a reputation as a reliable vehicle. Regardless, engine problems can occur, especially in older models or vehicles subject to improper maintenance. One such problem is a leaky or blown head gasket, and it is important to know the signs and symptoms of this problem in order to avoid a serious and potentially expensive problem to repair.

The head gasket forms a seal between the engine block and the engine head cover. It must keep engine exhaust gasses, engine oil, and cooling fluid separated in their proper passages. The symptoms of a leaky or blown head gasket are usually the result of these fluids mixing.

Fluid Leaking From Engine

    The appearance of oil or coolant on the outside of the engine at the interface between the engine block and the head cover can be a sign of a leaky head gasket. If fluid is visible in this area, wipe it off and run the engine for a while to see if the fluid reappears in order to confirm that it is a leak and not the result of a spill.

Exhaust Pipe Smoke

    Blue smoke coming from the exhaust pipe is a sign that oil is leaking into the cylinders. Thick white smoke, possibly accompanied by a sickly sweet odor, can be a sign that coolant is leaking into the cylinders. Both can potentially be caused by a leaking head gasket.

Foam or Sludge in Oil

    Foam or sludge in the engine oil can be a sign that coolant is leaking into the oil. Check the appearance of the oil on the dipstick. If it looks more like butterscotch pudding than engine oil then the oil may be contaminated with coolant. Look into the oil filler cap and check for signs of foam or sludge.

Dirty Engine Coolant

    Oil leaking into the engine coolant will impart a dark, oily appearance to the coolant and will cause an oily scum on coolant surfaces. Open the coolant reservoir cap (the radiator cap on older models) and check the appearance and condition of the coolant.

Bubbles in the Coolant

    Engine exhaust gasses leaking into the coolant passages will result in bubbles and foaming in the coolant fluid. With the engine cold, open the coolant reservoir cap (the radiator cap on older models). Start the engine and allow it to warm up to the point where the thermostat opens and the coolant begins to circulate. Have someone rev the engine a few times and look for bubbles in the circulating coolant.

Sluggish Engine Performance

    A blown head gasket can result in fouled spark plugs and reduced engine compression, both of which can cause rough engine operation and sluggish performance.

Senin, 21 November 2011

My Sentra SE-R Won't Start

My Sentra SE-R Won't Start

The SE-R is an options package available on the Nissan Sentra. If your Nissan Sentra SE-R won't start, there are several factors that could be to blame.

Ignition System

    Often times when a car won't turn over, it is due to a problem in the ignition system. These issues can range from something as simple as ignition lock by the steering system to more serious problems like a faulty alternator. If all the parts of the ignition system seem to be in working order, the problem could also be an issue of engine timing.

Fuel System

    While the Nissan SE-R is generally known to have a fairly cleanly running and efficient fuel system overall, the car has been subject to recalls related to the fuel pump. This recall affects cars within the 1991 to 1993 model years. Cars built during this time period are subject to fuel pump failure, which causes the vehicle to become unable to operate.

EGR System

    Many problems with the SE-R result from the vehicle's exhaust gas recirculation system (EGR), which redirects exhaust gases back to an intake, decreasing combustion temperature in the engine and reducing nitrogen in the emissions. These gases, however, still have particulates in them that can easily collect deposits inside the engine and choke up the entire works. In very extreme cases, this can cause the car to become inoperable.

Mercedes S430 Radio Problems

The Mercedes S430 sedan was introduced to offer those interested in a more economical vehicle than the Mercedes S500 series. The S430 is still a luxury sedan that includes a premium sound system and power push-button features that are expected with a Mercedes. The S430, however, has been known for its slew of electrical problems, particularly with the radio.

Radio Will Not Turn On

    The radio for the Mercedes S430 has a digital display and either a single disc insert in the head deck itself, or a six-disc CD changer located in the truck. Sometimes the radio will not turn on, leaving the CD function locked on the radio. This seems to happen only with the CD-changer versions of the S430. Turning the car off and back on seems to rectify the problem, but will happen randomly after that.

CD Changer Will Not Register the Remote

    The CD changer that is part of the radio in the Mercedes S430 will not respond to the CD changer remote in some cases. Instead, the CD changer shuffles through the songs in order. Even though the radio is part of this factory package, the CD-changer remote is the only way to change the songs on the CD changer. The CD changer can be switched to the radio, however, from the function on the radio itself.

Auto Shuffle Issue

    Mercedes radios have a unique feature that allows you to program nine stations into your radio for quick play, displaying all nine stations so that you can easily maneuver to the station you want to listen to. At random points when operating the vehicle, the radio will go into auto shuffle, bouncing between the stations rapidly. Normally, shutting the radio off for a period before turning it back on seems to fix this problem.

Minggu, 20 November 2011

How to Troubleshoot the Neutral Safety Switch on a 1997 Jeep Cherokee

How to Troubleshoot the Neutral Safety Switch on a 1997 Jeep Cherokee

The neutral safety switch in your Jeep Cherokee is designed to prevent the vehicle from starting with the gear selector in any position except "park" or "neutral." The switch utilizes three terminals and provides a ground to the starter solenoid circuit in the center terminal only. A malfunctioning neutral safety switch can have several symptoms revolving around the gear shift indicator.

Instructions

    1

    Sit down in the Cherokee and apply the parking brake. Hold the brake pedal down with your foot.

    2

    Try to start the vehicle in every gear. If the engine starts with the gear selector in positions other than "park" or "neutral," the neutral safety switch needs adjustment or replacing.

    3

    Have an observer verify that the reverse lights operate when the gear selector is in "reverse." If not, and the fuses and bulbs are in working order, the neutral safety switch is likely at fault.

    4

    Check the steering lock to verify that it will only allow the ignition key to go into the "lock" position when the gear shift lever is in "park." The key should only be able to be removed in the "lock" position.

Signs of a Faulty Fuel Pump

Signs of a Faulty Fuel Pump

Fuel pump problems can be hard to diagnose because the symptoms mimic other problems. A fuel pump should last as long as the vehicle, but sometimes it will fail because of a plugged fuel filter or from dirt and rust inside the gas tank. To prolong the life of your fuel pump, never run your vehicle out of gas. It is also a good idea to change the fuel filter as often as your owner's manual or mechanic recommends.

Signs of a Faulty Electric Fuel Pump

    Common signs that your electric fuel pump is failing include engine hesitation while running, engine misfires and low power when stepping on the gas. The vehicle may stall but restart when the engine has cooled, or it may crank but not start at all. Electric fuel pumps pump gas from the gas tank to the injectors. A high amount of pressure must be kept so the injectors can spray the fuel into the engine. Most electric fuel pumps are inside the gas tank, and some vehicles will even have two -- one inside the tank and one on the outside of it.

Signs of a Faulty Mechanical Fuel Pump

    Mechanical fuel pumps, commonly found in older vehicles, take gas from the gas tank and push it into the carburetor when the engine is being started or running. The most common signs of a bad mechanical fuel pump include low power or the vehicle not starting at all. Another way to check for a faulty mechanical fuel pump is to check the oil. There is a diaphragm located in the pump, and over time it may rupture, causing gas to leak into the crank case. If this happens, the gas will thin the oil and raise the oil level. You will also notice the oil smelling like gasoline.

Spark Plugs

    Another sign of a faulty fuel pump is dry spark plugs. After your vehicle has run, check one or two spark plugs to see if there is fuel on the plug. If there is not, the fuel pump is not getting gas to the engine.

Sabtu, 19 November 2011

How to Check Headlights

If the headlights on your vehicle are not functioning, one of four main electrical components may have failed: the headlight bulbs themselves, the wiring harness bringing power to the headlights, the fuses that protect the headlights from power surges or the headlight switch on your console. These components should be checked when troubleshooting any problems with your headlights.

Instructions

    1

    Replace the headlight bulb in the headlight assembly if the headlight is not coming on. If the headlight is still not working, continue to the next step.

    2

    Check the headlight's fuses. Most fuse boxes are on the left side of the engine compartment. Replace them as needed. If it is still not working, continue to the next step.

    3

    Connect the negative lead of your voltmeter to the negative terminal of the battery, and the positive lead to the positive lead of the wiring harness bringing power to the headlight. Verify that power is coming through the wiring harness. If no power is coming through, replace the wiring harness and test the headlights again. If they still do not work and power is coming through the harness, continue to the next step.

    4

    Replace the headlight switch. Remove the screws mounting the headlight switch, disconnect the wiring harnesses from the back of it and install the replacement headlight switch. Test your headlights.

Kamis, 17 November 2011

What Happens If Clutch & Pressure Plate Are Misaligned?

Drivetrains work by spinning; crankshafts spin, transmission input shafts spin and so do driveshafts, axles and wheels. Ideally, they should all spin together and in perfect synchronization, but misalignment between the crankshaft and clutch plate will cause some parts to spin on one axis, while other parts continue to spin on another. The symptoms are distinct, but the problem itself is easy to mistake with other issues.

Vibration

    If you've ever taken a back massager apart -- and who hasn't, really? -- then you've seen how it basically works. A massager gets its bounciness from a weight attached to a short arm, which is attached at its other end to the electric motor's shaft. A misaligned clutch plate will do the same thing in your transmission, but in this case, the "weight" is the clutch disc and the "arm" is the distance between the center of the disc and that of the flywheel. Though in this case, the clutch is usually tilted, as opposed to being lifted off of its axis parallel to the flywheel.

Clutch Chatter

    "Clutch chatter" is what happens when the clutch rapidly bounces on and off the flywheel, repeatedly grabbing and releasing it -- this is one of the tell-tale signs of a misaligned or damaged clutch mechanism or bearing. In the "damaged clutch mechanism" category, you also have things like oil or water in the clutch material, degraded friction material, a warped or damaged flywheel. this effect becomes even more pronounced over time, as the chattering clutch damages the pressure plate springs and weakens proper engagement.

Grab

    The clutch may bounce quite a bit before it does finally catch, but when it does, it'll do so with a vengeance. Normally, your pressure plate springs would push the clutch against the flywheel; but when the clutch is misaligned or cocked at an angle, it'll fail to engage until the levering force of its off-axis engagement wedges the plate against the flywheel. When that happens, the clutch will latch onto the flywheel and rapidly grab it instead of smoothly engaging it.

Improper Release and Net Effect

    Excess play in the clutch mechanism, combined with the wedging effect, makes the clutch difficult to release and modulate. Ultimately, you wind up with a clutch that works like an on/off switch and chatters during engagement. Misaligned clutch plates are death for the clutch pressure plate springs, the throwout bearing and often the transmission -- so, if you suspect that a problem is brewing, get it dealt with before a $500 problem turns into a $5,000 problem.

Rabu, 16 November 2011

How to Troubleshoot a Mazda MX6

How to Troubleshoot a Mazda MX6

Sharing many components with its Ford counterpart, the Probe GT, the Mazda MX-6 was a sporty two-door coupe produced during a nine-year period from 1988 to 1997. Slotted between the Miata roadster and RX-7, the front-wheel drive MX-6 gave consumers a combination of luxury and performance, plus a dose of fresh styling. It was powered by a small displacement double overhead cam V-6 engine that produced 164 horsepower, and could be ordered with a choice of automatic or manual transmissions. The car was generally reliable; however, older examples suffered from a variety of issues (mostly due to worn components), that can easily be identified through a series of relatively simple steps.

Instructions

    1

    Attach a universal code reader to the MX-6's diagnostic terminal to quickly track down any faulty or failing components.

    2

    Replace the air/fuel filters and ignition system components (spark plugs and wires) to help restore normal operation and overall vehicle performance. This will also cure a variety of symptoms such as low idle, hesitation or stuttering and poor fuel economy.

    3

    Replace all critical system fluids (engine oil, transmission, brake, coolant). This not only address problems with high engine temperature, gear grinding and brake fade, but also keeps your MX-6 running at peak efficiency.

    4

    Connect an automotive multimeter to check your vehicle's electrical system for any weaknesses. If the battery produces less than 12 volts when fully charged, it can no longer adequately power your vehicle's critical systems and needs to be replaced.

How Dangerous is a Bad CV Joint?

How Dangerous is a Bad CV Joint?

The CV joint, also known as a constant velocity joint, is integral to the proper motion of the wheels on a vehicle. Properly kept up, a CV joint can last upward of 100,000 miles; however problems have been known to occur at much lower mileages where care is not as thorough.

Cause of Joint Failure

    When the boot protecting the CV joint is torn, the lubricant which protects the joint and keeps it operating smoothly leaks out. When the lubricant has fully run out, the friction produced by the metal-on-metal motion of the joint can cause difficulty in steering, wobbling in the wheel(s), or even prevent any further motion at all.

Implications

    Any of the above problems, particularly if the wheel was to stop moving altogether, can cause an accident. On a road that is not crowded or prone to much traffic, this could simply cause a breakdown, and not necessarily an accident.. On a busy road, however, such an issue occurring could certainly cause an accident involving another vehicle.

Prevention/Solution

    At routine inspections, make sure the mechanic checks the CV joint boot for any tears. If there is already a problem, bring the vehicle to a mechanic as soon as possible to repair the damage and avoid an accident.

Selasa, 15 November 2011

1998 Nissan Pathfinder Brake Problems

1998 Nissan Pathfinder Brake Problems

The 1998 Nissan Pathfinder has been rated as reliable by Edmunds, and the only recalls on the Pathfinder have been for the front headlights and the filler pipe on the gas tank. Car Complaints shows no Pathfinder owners commenting about brake problems, indicating that any brake problems with the vehicle are from general wear and can be overcome with a proper service schedule.

Brake Pads

    A 1998 Nissan Pathfinder will wear the brake pads over a period of time. The brake pads close onto the brake rotors, causing friction that wears the pads. Driving in the city will wear the brake pads quicker than driving longer miles on the freeway because the Pathfinder is forced to make more frequent stops. When the break pads become too worn, the owner will hear a squeaking or scraping noise when the brake pedal is applied. If the scraping noise is heard when the Pathfinder is driven normally, then the brake pads need to be replaced immediately. Once this squeaking noise is heard, it is time to get the pads replaced before the pads do damage to the brake rotors.

Brake Rotors

    The brake rotors on a 1998 Nissan Pathfinder is what actually stops the wheels from turning when the brake pedal is applied. Applying the brakes not only wears down the brake pads, but also puts a groove into the brake rotors. Even though the rotors last longer than the brake pads, the rotors need to be checked to determine if they are worn too much and if they need to be replaced or turned. Turning the rotors is a less expensive way of changing out the rotors. The rotors develop a groove, but if there is enough thickness left in the rotors, the rotors can be removed and shaved down smooth again, which is referred to as turning the rotors.

Vibration When Braking

    If a 1998 Nissan Pathfinder begins to vibrate when the brake pedal is applied, it indicates that the new brake pads have not been put on correctly. This vibration occurs if the brake pads have not been aligned correctly with the brake rotors. The Pathfinder owner will have to take the vehicle back to the mechanic to have this corrected. The mechanic has to remove the brake pads and realign the pads to the calipers and brake rotors. The brake pads clip onto the brake calipers and can become slanted if the brake pads are not clipped on properly. If this vibration problem is not corrected as soon as possible it could create more heat to the rotors, causing them to warp or crack.

Air in Brake Line

    A brake line runs to the brake calipers and is filled with brake fluid, which is used to close the calipers that press the brake pads against the rotors. When there is air in the brake lines, a 1998 Nissan Pathfinder's brakes will become spongy or have a lot of play in them before the brake pads are engaged. This air gets into the brake lines when the lines have not been properly bled. A mechanic will remove the brake fluid drain plug located on each brake caliper, which allows them to loosen the pads and calipers so the pads can be removed. When the mechanic puts the pads and calipers back over the rotors, she fills the brake fluid reservoir with more brake fluid. The mechanic will press on the brake pedal until a complete line of brake fluid shoots out of the drain plug, a process which removes all the air out of the brake line. This procedure removes the play and spongy feeling the owner gets when pressing the brake pedal.

How to Test a Solenoid for an Outboard Motor

How to Test a Solenoid for an Outboard Motor

The solenoid on an outboard engine has the important function of transmitting battery voltage to the starting motor. When the contact inside the starter solenoid activates electronically, a circuit opens that passes electrical current from the battery to the starter, which turns the engine over. Shorts or disconnected wires on the solenoid can prevent the engine from starting. A fairly simple component, the solenoid can be checked for proper operation using a few simple tools and steps.

Instructions

    1

    Pull off your upper engine case, unclasping the cowl snaps by hand. Use a socket and wrench if the upper case has bolts. Make sure your lanyard cut-off switch has not been activated so that when you turn the ignition key the engine will start. Pull the spark plug boot from the tip of the spark plug; pull all spark plug boots if the engine has multiple cylinders. Connect coat hanger wire to the inside of the plug wire connector and ground it against the engine block. Ground all plug wires in similar fashion.

    2

    Place the positive lead from a voltmeter to the positive side of the main battery. Connect the negative lead of the voltmeter to bare metal on the engine. Look for at least 12.6 volts or more. Any reading less will require you to charge the battery to full capacity.

    3

    Check your cabin fuse box. Make sure the starter fuse or relay sits tight in their connectors and that the fuse element has not blown. Replace any fuse or relay that looks bad. You exchange the starter relay with another similar relay in the fuse box, then test for starter operation. If the engine starts, the relay was bad.

    4

    Look for the starter solenoid next to the starter on the engine block. Refer to your owner's manual for its precise location. Place the voltmeter positive lead to the large "Bat" connection (usually a red wire) on the solenoid, with ignition key in the "on" position. Look for 12.6 volts. If if does not read 12.6 volts, check the fuse box wires and the main electrical cut-off switch. Turn the key off.

    5

    Place the voltmeter positive lead to the smaller wire terminal on the solenoid (usually purple or yellow), and the voltmeter negative lead to a ground source. Have your assistant turn the key to start the engine. The voltmeter should read 12.6 volts or more. Listen for the solenoid to click and the starter to spin. If you do not have 12.6 volts and the starter does not spin, you have a problem with the ignition switch.

    6

    With the ignition key on, place the end of a jumper wire on the large "Bat" terminal on the solenoid. Place the other end of the jumper wire on the second solenoid post. If the solenoid has three posts, you will jump the two largest terminal posts on the solenoid. If the solenoid does not click or the starter does not spin, the solenoid has a defective short and must be replaced. If the solenoid clicks but the starter does not spin, the starter has an internal short and must be replaced.

How to Reset an Error on a 2000 Neon

How to Reset an Error on a 2000 Neon

Checking engine codes yourself on your Dodge Neon's computer is a fairly easy process. Doing so will keep you informed of your car's performance and what you should consider fixing or working on. However, once you get the code, translate it, diagnose it, and then attempt to fix it, you'll need to reset it to see if your attempt actually worked. In just a couple of steps, you can do just that and keep your car on the road.

Instructions

    1

    Release the car's hood by pulling the lever located below the steering wheel and off to the left.

    2

    Go to the hood and reach each hand under the hood around the center. Find the final release lever under the hood, typically on the left, and pull it up. Raise the hood and prop it with the prop rod found in the front of the engine bay.

    3

    Disconnect the negative (black) battery cable for two minutes and then replace the cable.

    4

    Start the car and look for the check engine light.

How to Repair & Troubleshoot an S-10 Chevy 2.5 Engine That Starts Then Dies

How to Repair & Troubleshoot an S-10 Chevy 2.5 Engine That Starts Then Dies

Troubleshooting and repairing a 2.5-liter-engine in an older model S-10 Chevy that starts then dies may require you to replace a number of parts and make several adjustments, or it may be as simple as basic maintenance. The fact that the engine starts and then dies indicates that there's a fuel issue. That means you want to begin your inspection around the carburetor. There are several troubleshooting tests, the results of which will tell you why your S-10 is not getting gasoline to the engine.

Instructions

    1
    Adding gasoline is always a good place to start.
    Adding gasoline is always a good place to start.

    Add gasoline. Sometimes the fuel gauge gets stuck on S-10s and you do not realize it. Unfortunately, there is still enough gasoline in the tank to allow fumes to drift into the fuel line and the Chevy will fire for a moment and then die and you think it has gas in the tank.

    2
    Fuel filters go bad on all vehicles, test the one on your S-10.
    Fuel filters go bad on all vehicles, test the one on your S-10.

    Remove the fuel filter which is on the fuel line. There is a casing with two hose clamps. Inside the casing is the filter. Remove it and reattach the casing to the fuel line with the hose clamps. Start the engine. If it continues to run without dying, you have a clogged fuel filter. You do not want to run your Chevy without a fuel filter for long or you risk damaging the engine, but this test will tell you if the fuel filter is bad.

    3

    Check the fuel pump and the integrated relay control module. With one test, you can diagnose both. Remove the relay running from the fuel pump to the IRCM from the IRCM box. Attach your electric relay test cable to the electric relay module running to the pump and attach the other end to the positive terminal of your battery. If the fuel pump is good, you will hear it begin running and you can assume the problem may be your IRCM. If you do not hear the pump run, you have a bad pump.

    4

    Remove the pan to your air filter from the top of your carburetor. Have someone step on the pedal repeatedly while you look down into the carburetor. Make certain the choke is not stuck closed.

    5

    Replace the entire fuel line if all else fails.

Senin, 14 November 2011

How to Diagnose Transmission Noises

How to Diagnose Transmission Noises

Although most vehicle transmission noises relate to internal parts and cannot be seen, their behavior and sound frequency always deal with a moving part according to engine rpm or pressure. Other worn vehicle parts can mimic the noise or feel of faulty transmission parts, so it becomes important how to identify noises specific to certain problems.

Instructions

    1

    Drive the vehicle, making numerous stops and accelerations. If you hear a constant whining noise, accompanied by a slip in the gears as the transmission automatically shifts, it points to low transmission fluids. Without the proper fluid level, the pump has to push air through the transmission, which causes the noise and produces the hesitation or slippage. Any leaks on the ground will confirm a loss of transmission fluid.

    2

    Sit in the vehicle with the engine idling and the shifter in park or neutral. Keep your foot off the brake pedal. Push the accelerator pedal, gently raising the engine rpm. If you notice a humming noise that increases in intensity as the engine rises in speed, it points to a malfunctioning transmission pump or pump shaft. Since the gear train has not been engaged in drive, it rules out all the other components. Consult your repair manual for the location of these components.

    3

    Listen for a buzzing noise while you have the engine idling and in gear with your foot on the brake. This puts the torque converter in operational mode. Since the torque converter pump, stator and turbine spin freely without engagement during neutral or park, the noise will not be present in those settings. Accelerate slowly in drive and listen to whether the torque converter noise will get quieter as the vehicle moves forward.

    4

    Place your foot on the brake with the engine in neutral and idling. Raise the rpm slightly over idle. Put the shift selector in drive, while maintaining pressure on the brake. If you hear a loud clunk, or feel a chassis shudder, this could indicate that the torque converter mounts have disconnected or broken. Confirm this by checking the tightness of the universal joints, both front and rear of a rear-drive vehicle.

    5

    Listen for a heavy clunk when shifting from neutral to reverse and back again. Check the transmission cross member mount (rubber dampers) for excessive wear or splits. A noticeable vibration in the chassis frame during the heavy clunk will point more toward a defective transmission mount rather than a torque converter problem.

    6

    Drive the vehicle through its normal transmission shifting range from first to overdrive. Use some fast acceleration, allowing the transmission to firmly shift. Listen for any rumbling, growling or mechanical metal-to-to metal noise in each gear just after it shifts. Such noises indicate problems with the individual planetary gears, input shaft or interior transmission bearings. A single gear can be chipped or worn down, allowing only a noise in that gear. Consult your repair manual for the location of these parts.

Where Is the DTC Port Located in a 2000 Honda?

The DTC port in a 2000 Honda will always be in the front of the vehicle. The location varies by the model, so you'll need to research your specific Honda to get an exact location, but the DTC port is usually either below the steering wheel, behind the mini console or behind the ashtray in 2000 Hondas.

Identification

    The letters DTC stand for "Diagnostic Trouble Code." A Honda's on-board diagnostic system issues a DTC when something goes wrong with the engine. A Honda manufactured in the year 2000 will operate under OBD-II codes.

Function

    The DTC port can be used with an OBD-II scanner. This device features a cable and a multi-pronged plug that will fit into the DTC port. The two computers interface with each other once the scanner and the Honda are turned on, and the reported trouble codes will appear on the scanner's screen.

Considerations

    Software and downloads can turn a laptop into an OBD-II scanner. This requires a standard software installation like any other program, but you'll also need to buy a diagnostic cable with a 16-pronged plug on one end and a USB plug on the other. Once the software is installed, the laptop will function like a scanner.

Minggu, 13 November 2011

What Happens If My EGR Is Blocked Off?

What Happens If My EGR Is Blocked Off?

EGR, which stands for Exhaust Gas Recirculation, comes equipped on most new vehicles, as well as some older models. The EGR valve recirculates burned exhaust emissions back into the intake system so the emissions can be re-burned, or "recycled," out the exhaust. The system operates by the opening and closing of solenoid valves, regulated by a diaphragm. The solenoid valves open and close the EGR by the amount of manifold pressure the valves receive. When the EGR valve is blocked off or completely closes, it will show some obvious signs.

Pinging or Knocking

    A clogged or closed off EGR valve will sometimes give off an audible noise resembling a "pinging" or light "knocking" coming from the engine. The trait is nearly similar to pre-ignition or detonation, both caused by abnormally high combustion chamber temperatures. A clogged EGR valve will raise the combustion temperature the same way and can create this sound.

Rough Idle

    A clogged ERG valve will manifest itself in the idle circuit. When the EGR passageway becomes blocked off it keeps exhaust emissions and air from circulating in the engine, causing a suffocating condition. The engine idle will be rough, frequently stumbling and unable to hold a steady idle rpm. The rpm may be sporadic, raising and lowering randomly.

Stalling

    Stalling, a complete engine shut-off condition, can happen when the EGV has clogged, shutting off the flow of emission gases. This will happen most predominately at idle ---and may not happen all the time.

Overheating

    The exhaust produced by the combustion process contains carbon dioxide, which is partly water. The carbon dioxide, along with burnt exhaust gases, enters through the EGR valve into the intake to reduce harmful NOx (nitrogen oxide) emissions, but it also cools the combustion chamber. If the EGR has clogged, it will allow a noticeable temperature rise in the engine.

Smog Test

    If the EGR valve is clogged or completely blocked off it can longer re-burn harmful emissions in the combustion chamber. The NOx emissions will flow unregulated through the combustion chamber and out of the exhaust pipe. The excessive NOx emissions will show up during a smog test and cause a failure. In addition to the NOx emissions, a clogged EGR could enrichen the fuel mixture and produce excess amounts of HC (hydrocarbons) and CO (carbon monoxide).

Engine Light

    A clogged or defective EGR valve will trip a "Check Engine" or "Emission Control" light on the dashboard. The owner will have to take his vehicle to a certified test and repair station that has a code scanner. The scanner will then be plugged into the vehicle's computer system, and a trouble code will be identified. If the EGR valve represents the system failure, the code number will specifically identify the EGR as the failed component.

Sabtu, 12 November 2011

Transmission Trouble Symptoms

Transmission Trouble Symptoms

Transmission problems can be lead to expensive car repairs, so paying attention to warning signs and symptoms of potential issues can save you a lot of money. Repairing a small problem like a leaky valve is a lot cheaper than replacing an entire transmission after all the fluid leaks out and the transmission seizes. Be on the lookout for the early signs of transmission troubles, and repair them as soon as possible.

Fluid problems

    A light reddish fluid leaking from under the engine is a sign that the transmission is in trouble. It might indicate that the transmission case has cracked, or that a valve is leaking. If the transmission fluid gets too low, the transmission will seize up and the repair costs will be significant. Top off the transmission fluid daily until the leak or problem is fixed.

    Clean transmission fluid should be a light reddish color. A dark and muddy color means the fluid is old and needs to be replaced. If it isn't replaced, eventually the fluid will get too sticky to keep the transmission running properly. Get a transmission fluid change as soon as possible to prevent further damage.

Performance problems

    Slipping gears are a major sign of a transmission problem. If you press on the gas or brake and the car is slow to respond, it is an indication that the gears are slipping. This can be a result of low transmission fluid or a mechanical failure. Have the transmission looked at immediately before it gets worse.

    When transmission fluids are low, knocking sounds can sometimes be heard coming from the transmission. Check and refill the transmission fluid immediately.

Odor problems

    A burning smell could indicate the transmission fluid is leaking from a valve or hose onto the exhaust system. Burning coolant will usually result in a sweet smell, while burning transmission fluid tends to have a strong burnt toast smell. This can result in a dangerous fire if not repaired immediately.

    White smoke coming out of the tailpipe is an indication that the vacuum hose coming from the transmission is leaking or defective. The transmission fluid is being burned and will probably give off a bad odor. This typically happens on older automatic transmissions. Have the hose replaced immediately.

Troubleshooting Code P0340 on a 2000 Dodge Neon

Troubleshooting Code P0340 on a 2000 Dodge Neon

Modern vehicles use on-board diagnostics (OBD) to monitor a vehicle's components, and to relay issues via OBD-II codes to a central computer. Different elements within the system produce different codes. Dodge Neons use manufacturer specific codes in addition to generic codes. Code P0340 indicates a short or open in the camshaft position sensor circuit, a damaged camshaft position sensor, an issue with the camshaft, a damaged timing chain, or an issue with the Electronic Control Module (ECM). Troubleshooting the cause is a multiple step process.

Instructions

    1

    Check the resistance in the camshaft position sensor circuit using an ohmmeter. Disconnect the camshaft position sensor (a two-pronged male connection going into a female connection, located beneath the manifold adjacent to the camshaft) and insert the ohmmeter terminals into the female connection. Resistance cold should be between 835 to 1400 ohms. If the engine is warm, it should be between 1,060 and 1,645 ohms. If the resistance is outside of those levels, replace the sensor.

    2

    Check for an open or a short in the male connection. Trace the line to where it connects to the vehicle's computer (near the battery). Disconnect the line from the battery and plug one end of the ohmmeter into the sensor side and the other end of the ohmmeter into the computer side. Check for continuity (the resistance should register less than one ohm). If the measurement is higher than one ohm, replace the cable. Also inspect for damage to the harness on both ends. Any damage or corrosion requires replacement.

    3

    Visually inspect the timing belt. Remove the access plug from the top portion of the timing belt cover (located on the side of the engine towards the top near the firewall) and visually inspect the timing belt. Verify that you can see the belt and it appears tight. If you do not see the belt, it has broken or slipped.

    4

    Replace the access plug. If all aspects of the diagnosis check out, the timing is likely off on the engine. Correcting the timing will repair the issue.

Symptoms of a Bad Water Pump in a 1987 Toyota 4Runner

Symptoms of a Bad Water Pump in a 1987 Toyota 4Runner

The water pump on a 1987 Toyota 4Runner is externally mounted and is run by the serpentine belt. The function of the water pump is to push the fluid through the radiator and all of the cooling veins of the engine. When the water pump goes bad in your 1987 Toyota 4Runner, there are several tell-tale symptoms.

Overheating

    When the water pump begins to go bad; the first thing you will notice is that the truck will overheat. Depending on what part of the pump went bad, it can happen intermittently or all of the time. There are other items to check before replacing the water pump as they can cause a similar issue: coolant level, thermostat and cooling fan, for instance.

Noise

    Because the 1987 Toyota 4Runner has an externally mounted water pump, you can audibly hear if it has failed. Typically, when a water pump fails, there is a bearing that has either ceased or fallen apart. This will make a loud grinding, growling or squeaking sound from the front of the engine.

Belt Tracking

    Another symptom of a failing water pump is when the pulley has partially detached from the pump. A sign of this is if the serpentine belt continuously falls off or you can see the belt moving in various directions on the pulley.

Leaking

    All externally mounted water pumps include a weep valve. This valve is designed to open when the bearing on the water pump has failed. When this valve opens up, it will allow a few drips of coolant per day to alert the driver of a problem. A water pump can also leak when the casing has failed. Water pumps are generally cast from steel, so they are not invincible. Over time, the heating and cooling will weaken the metal and it can crack, causing a leak.

Screeching Belt

    A constantly screeching belt is a sign that a serious problem exists. When a pulley locks up completely, the belt will continue to spin as the engine turns. The spinning of this belt over the stopped pulley will make a loud screech. When a water pump bearing completely locks up, this noise can occur.

How to Use a Mechanic's Stethoscope

A mechanic's stethoscope works the same way as a doctor's stethoscope. It's designed to pinpoint problems in the engine when you cannot visually pinpoint the location of a noise. These stethoscopes are used by professionals and hobbyists for common problems, such as locating engine knocks, air leaks and bad bearings. If you like to work on cars, a stethoscope may save you time finding the location of a problem.

Instructions

    1

    Pinpoint noise in the engine compartment. If you have a knocking sound, or some other inappropriate noise in the engine compartment, perform a diagnostic sweep of the engine compartment. Leave the car running. Without the stethoscope, start in one corner of the engine compartment and slowly move across the engine, listening for the general vicinity of the noise. Listen to the individual engine components in that region for internal noise (such as engine block, alternator, A/C compressor, power steering pump, and master cylinder) by donning the stethoscope and probing the part in question.

    2

    Check the the transfer case. If odd sounds come from the back of your rear- or four-wheel-drive vehicle, you may have a problem in your transfer case. Make sure that the brake is on and the vehicle is on a flat surface, with the wheels chocked, and the transmission in neutral. Do this while the engine is off and the rear tires are off the ground. Have an assistant spin the rear wheels by hand as you listen. Place the sound collector directly on the different sections of the transfer case and listen for unusual sounds.

    3

    Check for vacuum leaks or pressure leaks. You can also use the stethoscope to detect leaks in the vacuum hoses, brake lines, and other lines that are under pressure. Using an assistant to apply the brakes or rev the engine, test the areas in question one at a time until you hear a hissing sound.

    4

    Check your wheel bearings or brakes. While the engine is turned off and the wheels are off the ground, slowly rotate a wheel and listen for grinding noises.

Jumat, 11 November 2011

Car Problems: No Heat

Car Problems: No Heat

If you live in a cold climate and don't have the luxury of a garage, not only will your vehicle be harder to start but you are going to want to turn on the heat once you get in. Without a working heater in your car, that dreaded Monday morning commute can become a literally numbing experience. As counter-intuitive as it sounds, if the heat in your vehicle is not working, most likely there is a problem with the cooling system. There are a couple of steps you can take to diagnose the reason and get some heat back in your car.

Instructions

    1

    Check your engine's coolant level. When a vehicle is running, the heat that is produced by the engine is absorbed by the coolant and flows to the radiator inside the car. If the coolant is low, that flow is stopped. Simply top off the coolant and the problem should be resolved.

    2

    Look for any debris trapped in the heater hoses or heater core. Turn on the heat control in your vehicle to full temperature but make sure the fan is off. Open up the hood and locate the heater hoses. There will be two of them at the rear of the engine about 1 inch in diameter. Feel the hoses: they should be roughly the same temperature. If there is a big difference in temperature, something most likely is blocking the system, or there could be a leak. It's best to get your car serviced.

    3

    Watch the engine temperature gauge. If your vehicle takes a long time to warm up or does not warm up enough, the problem is probably a faulty thermostat. A healthy engine temperature gauge should warm up to about the half-way point after six to eight minutes of the engine running.

    4

    Test the actual temperature controls inside the vehicle. If they are not performing properly and you are fairly sure that the coolant system is in working order, the problem probably lies in the controls. Heater controls usually operate with cables, vacuums or electronics. A problem with the control system usually means a trip to the garage for service.

Kamis, 10 November 2011

What Causes a Broken Piston on an Outboard Motor?

What Causes a Broken Piston on an Outboard Motor?

Outboard boat motors endure a lot more stress, heat and wear than automobile engines. Usually operated at full-throttle, outboard motors do not idle or coast often. Contained in the power-head of the outboard motor, the piston receives the highest stresses and heat during operation. Several issues, all related to stress and heat, can cause a piston in an outboard motor to break.

General Oil Lubrication

    Oil used in an outboard motor must keep its viscosity (thickness) and lubricating qualities to form a protective barrier between major engine components such as rod bearings, piston pins and crankshaft bearings. If the oil becomes contaminated, it allows metal-to-metal contact between engine parts, particularly the piston and rod. Inadequate lubrication causes friction and excess heat, which can expand the piston skirts and jam it in the cylinder head, cracking the piston.

Connecting Rod Failure

    In an outboard motor, a connecting rod attaches the piston to the crankshaft to allow reciprocal motion. The large end of the connecting rod connects to the crankshaft. If the connecting rod bearings receive little or no lubrication, they become worn and open a gap between the rod bearing and the crankshaft journal. Such an opening will cause a pounding effect that gets progressively worse until the rod snaps free. The force of the break can send the rod upward to strike and break the piston.

Piston Pin Failure

    A piston pin connects the top of the connecting rod to the body of the piston. It allows the piston to rotate on its axis, while the lower part of the connecting rod follows the rotation of the crankshaft. If the piston pin bearing sleeves wear, the rod can break free from it and fly upward to puncture a hole through the piston body or skirt.

Piston Ring Failure

    Piston rings function as circular metal seals that keep combustion gases from passing out of the piston into the crankcase. If the piston rings bind or gall as a result of wear, age or lack of lubrication, they can break off in pieces and become trapped between the piston top and cylinder head. The collision of the broken ring and piston frequently cracks the piston face or edges.

Pre-Ignition

    Pre-ignition can occur in two-stroke or four-stroke outboard motors. It happens when the air-fuel mixture introduced into the combustion chamber ignites prematurely. Pre-ignition occurs when a hot spot develops on the piston face, valves or cylinder head. The hot spots can also be caused by glowing deposits anywhere in the combustion area. Spark plugs that have the wrong heat range, or have worn electrodes, can cause pre-ignition. If prolonged, pre-ignition will cause a weakening of the piston face, leading to metallurgical failure.

Detonation

    Detonation occurs in the combustion chamber after the cylinder has fired. It results from a violent collision of one or more flames fronts which can cause an abrupt explosion. Heavy carbon deposits on top of the piston or valve faces, a lean air-fuel mixture, overly advanced timing and low octane fuel can all cause detonation. Detonation can be identified by an audible spark or carbon "knock" inside the power head. Serious cases of detonation can drive a hole down through the middle of the piston.

Engine Cooling

    If the outboard motor overheats as a result of a broken water pump impeller, rust-filled water passages or clogged raw water intake ports, the overall engine temperature can rise and overheat the piston. An overheated piston can freeze in the cylinder wall due to sever galling and cause the connecting rod to break free. An overheated engine can cause minute cracks in the piston body, due to the extreme expansion and contraction of the piston metal.

Gasoline Quality

    Gas that has sat dormant for over three months can cause heavy gum and varnish deposits in the cylinder. The deposits can accumulate on the top of the piston, attracting carbon buildup. The additional deposits can become thick enough to raise the combustion ratio of the cylinder and cause overheating, pre-ignition or detonation. In addition, gas that has over 10 percent alcohol will cause piston overheating, leading to cracks or catastrophic piston failure.

Two-Stroke Oil-Fuel Mixture

    Outboard motors that require a mixture of oil to gas can suddenly overheat and disintegrate the piston if the ratio mix is not correct. A two-stroke outboard motor that does not have enough oil in the fuel mixture will run hot, increasing the temperature of the piston, valves and piston rings. Two-stroke outboard motors have no way to lubricate the upper power-head components, other than the fuel and oil mixture which enters the combustion chamber.

Valve Train Components

    An outboard motor has intake and exhaust valves that intake fuel and expel combustion gases. The valves have springs and keepers to hold them in place. If a keeper or valve spring breaks, it allows the the valve to float freely and strike the top of the piston. These impacts can crack the pistons and freeze the motors.

How to Tell Whether a Ball or Roller Bearing Is Bad

How to Tell Whether a Ball or Roller Bearing Is Bad

Ball and roller bearing help shafts and other parts rotate in vehicle components, motors and other equipment or machinery. They prevent direct contact between moving and non-moving components for easier operation, reducing stress and accelerated wear. Still, these bearings are subject themselves to a lot of stress, depending on the equipment they operate. As part of a maintenance schedule according to the manufacturer specifications, check them periodically for wear to prevent equipment damage.

Instructions

    1

    Turn on and operate the piece of equipment with the bearing you want to inspect, if the bearing is accessible. Bearings on air conditioner motors, blowers and similar equipment, for example, are accessible by removing a lid or cover. Use a Phillips screwdriver to remove the cover if necessary.

    2

    Contact the bearing housing with the tip of a mechanic's stethoscope, and listen for noise. Keep the stethoscope hose away from moving parts. Check at various points around the piece of equipment to ensure the noise is coming from the bearing, which will be the loudest point. If the bearing is making a noise, add the proper lubricant to the bearing, if possible, and test for noise again. If the noise remains, replace the bearing.

    3

    Turn off power to the piece of equipment with the suspected bearing, and remove any components such as covers or belts, if necessary, to gain access to the shaft or part with the bearing. On vehicles, for example, you can inspect a wheel bearing by raising the wheel/tire assembly off the ground using a floor jack and securing the vehicle with a jack stand under the frame.

    4

    Put on your mechanic's stethoscope, and manually rotate the shaft or wheel/tire assembly with the bearing you want to inspect while listening for noise. Check at various points near the bearing to ensure the noise is loudest in the bearing housing. If possible, lubricate the bearing according to the manufacturer's instructions. If the bearing is still noisy, replace it.

    5

    Remove the ball or roller bearing from the piece of equipment, if possible, after listening for bearing noises with your mechanic's stethoscope. Follow the instructions on the equipment's service manual to remove the bearing safely.

    6

    Wash the bearing in solvent, and let it air dry for a few minutes.

    7

    Inspect each ball or roller visually for pitting, chipping, rust and wear spots. Check the bearing cage or roller housing for bents or cracks. Manually rotate the bearing next to your ear, and listen for noises. If you detect any minor damage, wear spots or noises, replace the bearing.

    8

    Check the bearing race as well if your piece of equipment is equipped with it. (The race is the outside steel ring where the bearing rotates as the machinery or equipment operates.) Inspect the race for hard posts, cracks, wear spots or any other indication of damage. If the race is damaged or worn out, replace both the race and the bearing.

    9

    Lubricate or pack the bearing with grease according to the manufacturer's instructions and reinstall the bearing if necessary.

How to Troubleshoot Overheating in a Grand Am 2.4L

How to Troubleshoot Overheating in a Grand Am 2.4L

The Pontiac Grand Am 2.4 Liter four-cylinder engine is designed to run in hot and cold weather and stay within a normal range of engine temperatures. Excessive engine temperatures can cause a number of different major engine failures so don't delay finding the source of the overheating problem. The engine cooling system includes the radiator, surge tank, fan, fan motor, thermostat, drive belt and coolant. Always check the coolant while the engine is cold to prevent scalding injuries from hot coolant.

Instructions

Low Coolant Levels

    1

    Remove the cap on the coolant surge tank and check the coolant level in the tank. The tank is pressurized so release the cap slowly to release any pressure built up inside.

    2

    Add coolant to the FILL line in the surge tank.

    3

    Start the engine and let it run until it reaches normal operating temperature and add more coolant, if necessary.

Defective Drive Belt

    4

    Inspect the serpentine drive belt for tension and wear. Replace the belt if it is cracked or worn and adjust the tension if it is too loose or too tight.

    5

    Use your hands to inspect the drive belt for cracks or wear. Run your hands along the whole belt and feel for cracks, missing ribs and sections that have worn smooth.

    6

    Replace a defective belt by loosening the tensioner bolt with a wrench until the belt slacks off. Remove the belt and replace it with a new one. Follow the path shown in the diagram on the decal by the radiator.

    7

    Rotate the tensioner counterclockwise with a wrench to let the belt fit over it. Release the belt tensioner and it will automatically adjust the belt to the correct tension.

Blocked or Restricted Radiator Core

    8

    Inspect the radiator core to see if it is blocked by dirt or other materials, or if the fins have been bent and damaged to the point where they cannot transfer heat from the coolant to the outside air.

    9

    Clean the radiator fins if they are plugged. Use a pressure washer or hose and soft brush.

    10

    Bend damage fins so they are not pressed together or up against the metal pipes in the core. If the fins are too badly damaged the core may require replacement.

Other Overheating Problems

    11

    Inspect the upper radiator hose by feeling it when the engine is running. Always start with a cool engine. If the engine is running hot but the upper hose does not get hot then the thermostat is likely stuck in the closed position. Replace the thermostat.

    12

    Inspect the fan. The fan sits just behind the radiator and helps draw air across the radiator fins. If the blades are broken or damaged replace the fan. The fan is driven by its own motor rather than by the drive belt. A faulty fan motor will cause chronic engine overheating. Testing the motor involves a complex series of steps and special equipment and may require a professional mechanic.

    13

    Check the coolant surge tank cap to see if it is holding pressure in the cooling system. This engine does not have a pressure cap on the radiator itself. Listen for hissing at the cap with the engine running. Replace the cap if you can hear air escaping from the cap.

Transmission Problems in a 2000 Ford F-350

Because a 2000 Ford F-350 is a complex vehicle it can be difficult to troubleshoot what may be causing transmission problems. Two troubleshooting methods to use are to listen to the noises the truck makes and pay attention to the feel of the truck as you drive.

Check for Erratic Shifting

    Inspect the transmission modulator when the F-350's transmission has an erratic shifting feel to it. The modulator may be leaking fluid into the vacuum system of the transmission. If the modulator works properly, look at the transmission fluid level and type to ensure they are correct. Then check the transmission filter to see if it is clogged or dirty.

Listen for a Grinding Noise

    Look at the clutch assembly and clutch disc when the truck has a grinding sound as you change gears. The clutch pressure plate may be worn or damaged and need to be repaired.

Check for a Knocking Feel

    Locate the Ford's driveshaft when the truck has a knocking feel as you drive it. The driveshaft may be loose, bent or unbalanced.

Rabu, 09 November 2011

The Location of a Vehicle Speed Sensor in a 1997 Chevy Blazer 4.3L

The Location of a Vehicle Speed Sensor in a 1997 Chevy Blazer 4.3L

There are two types of vehicle speed sensors (VSS) on the 1997 Chevy Blazer. One is a single variable speed sensor that sends a signal to the digital ratio adapter control and cruise control. The variable speed sensor is responsible for the speedometer reading in the Blazer. The other type of speed sensor on the Blazer is the antilock brake system (ABS) wheel speed sensors. These sensors read the individual wheel speeds to communicate with the ABS system. Four-wheel, disc-brake model Blazers have four sensors. Rear-drum-brake models have only two.

Instructions

ABS Wheel Speed Sensors

    1

    Apply the parking brake on the 1997 Chevy Blazer.

    2

    Start the engine. Turn the steering wheel all the way to the right (to locate the driver's side front sensor). Shut the engine off.

    3

    Kneel by the driver's front tire and locate the thin black wire that comes down from the front frame rail and disappears behind the front wheel.

    4

    Crawl beneath the rear portion of the front left tire with a flashlight or shop light (if necessary). Follow the black wire to the ABS wheel speed sensor. The wire runs directly into the sensor behind the hub that contacts the cogged metal ABS ring. The right front (passenger side) speed sensor is located in the same place behind the passenger's side tire. Rear-wheel disc-brake models of the 1997 Blazer have speed sensors connected to the rear wheels the same way they connect to the front wheels. Rear-drum models do not employ rear-wheel speed sensors on the rear ABS system.

Variable Speed Sensor

    5

    Apply the parking brake on the Blazer.

    6

    Crawl under the Blazer directly below the driver's seat for two-wheel drive models or a little further back for four-wheel drive models. Have a flashlight or shop light at your disposal, if necessary.

    7

    Focus on the upper left (driver's side) tail shaft of the transmission of the two-wheel drive model or on the upper left (driver's side) tail shaft of the transfer case attached to the rear of the transmission on the four-wheel drive model.

    8

    Search for the wire harness coming from the front of the Blazer. The harness attaches to the sensor screwed into the transmission tail shaft or transfer case tail shaft. Identify the sensor by the 1-inch hex head at its base that is screwed into the tail shaft.

How to Troubleshoot the Handling of a Nissan

Some of Nissan's vehicles are supplied with a vehicle dynamic control system (VDC) to keep the vehicle on its steered path. Sensors monitor driver actions and the Nissan's movement. The computer will perform some braking, and change engine power depending on where it thinks you want to go. Problems with the handling of a Nissan can be related to the VDC system. These kinds of issues can be corrected by troubleshooting.

Instructions

    1

    Keep an eye on the dashboard for the indicators marked "SLIP" and "VDC Off" which will tell you the status of the computerized handling system if handling isn't normal. "SLIP" will blink when VDC is operating. "VDC OFF" means the system is off. Turn the VDC system back on if the Nissan's handling is poor by pressing the "VDC Off" button until the light goes out.

    2

    Adjust your driving if "SLIP" comes on. "SLIP" means the road conditions may be slippery. The VDC aids in steering and stopping, but be careful, even if VDC is engaged.

    3

    Remove any aftermarket suspension parts like enhanced shock absorbers if the "VDC Off" light comes on and handling is bad. The VDC system is geared for stock equipment and tires only. Use winter tires or snow chains on snow-covered roads. VDC won't substitute for the correct winter equipment.

    4

    Don't drive on very inclined corners with high banks and leave the VDC switch on if the handling is poor with VDC on. The system can't operate properly in that environment. Disengage VDC, or avoid those kinds of roads.

How to Reset the Check Engine Light on a 1995 Mercury Grand Marquis

Resetting the "Check Engine" light on a 1995 Mercury Grand Marquis is a relatively simple task for anyone with the prerequisite automotive repair knowledge. The "Check Engine" light turns on in response to diagnostic trouble codes stored in the Grand Marquis' powertrain control module. The final step in the repair process for correcting the faults that caused the codes is resetting the "Check Engine" light. While you can reset the light without actually repairing the malfunctions, this might cause more damage to the Grand Marquis.

Instructions

    1

    Sit in the Grand Marquis' driver's seat. Locate the datalink port just below the dashboard, and remove the black, rectangular-shaped plastic cover from the port.

    2

    Plug the scan tool's datalink cable into the datalink port by hand. Turn the Grand Marquis' ignition to the "Run" position to turn on the powertrain control module and scan tool.

    3

    Perform a quick test on the powertrain control module with the scan tool in the exact manner described in your scan tool's specific owner's guide.

    4

    Select the option to erase the codes when the scan tool queries whether you would like to erase them. Most scan tools have a button interface on the front cover that allows you to move between options displayed on the scan tool's view screen.

    5

    Complete the scan tool's quick test by following the scan tool's owner's guide. Turn off the ignition, and remove the datalink cable from the Grand Marquis' datalink port. Place the dust cover back over the datalink port by hand.

Selasa, 08 November 2011

Ford Explorer Ignition Problems

Ford Explorer Ignition Problems

Determining the ignition problems with a Ford Explorer is a step-by-step process, but if a person is not mechanically inclined it is best that the Explorer be taken to a qualified Ford technician. The Ford Explorer starting problems can be caused by other components besides the ignition module or coil. Once the battery and starter have been checked and determined to be in good condition, then the ignition switch, module or coil need attention.

Ignition Switch Corroded

    The Ford Explorer has an ignition switch that signals the starter to turn the engine over when the key is turned on the column of the vehicle. The switch can become corroded over time, creating an interrupted signal in the ignition switch. The steering column and ignition switch becomes hot to the touch when this corrosion problem occurs. The Explorer may occasionally start when this corrosion begins to occur, but replacing the ignition switch is the only way to ensure that this corroding problem on the ignition switch is corrected.

Broken Ignition Wire

    The ignition wires going to the starter in a Ford Explorer are located close to high temperatures when the vehicle is running. The wires can slowly begin to melt because of the heat generated from the engine. This melting of the insulation around the ignition wires causes some of the wires to break on the ignition, creating Ford Explorer ignition problems. The breaking of the ignition wire can develop over time, and the operator will experience minor or intermittent starting problems until the wires break completely. Changing the wiring harness that runs from the ignition switch and starting unit is the only cure for this ignition problem.

Loose Connection

    The wiring harness of the ignition of a Ford Explorer is attached by male and female plugs on the ends of the wiring harness. One or more of these plugs of the wiring harness can come loose and create Ford Explorer ignition problems. The operator or owner of the Explorer can open the hood of the vehicle and check the connections of the wiring harness. The operator does have to crawl under the vehicle to check the connections to the starter because it is located on the driver's side of the engine compartment on the underside of the engine.

Senin, 07 November 2011

Valve Body Transmission Problems

The valve body is a part of an automatic transmission that aids in the gear shifting process. But, like any mechanical device, problems may affect the valve body.

Function

    The valve body controls the timing of the gears within an automatic transmission. It uses a combination of fluid pressure detection and hydraulic signaling to control the changing of gears and the activation of the clutch.

Significance

    Though many parts can fail on an automatic transmission, symptoms of a damaged valve body include incorrectly timed gear shifts, or no shifting at all. The valve body consists of multiple springs and valves; if the springs fail, the valves cannot open and close.

Considerations

    A repair technician may rely on diagnostics tools to detect damaged components in a vehicle. If the valve body fails, an error code is sent to the vehicle's on-board computer. The diagnostics tool will read the code and offer assistance with the best repair strategy.

How to Tell If My Brake Master Cylinder Is Bad?

How to Tell If My Brake Master Cylinder Is Bad?

A leaking master cylinder will cause problems with your vehicle's entire braking system. A bad master cylinder can make a vehicle hard to stop and dangerous to drive, so it is important to repair or replace your vehicle's master cylinder promptly if you determine you have a problem with it.

Instructions

    1

    Open your hood, and check your brake fluid reservoir. If it is low and you have recently added fluid, you probably have a leak somewhere in your braking system. A leaking master cylinder is a failing master cylinder, so you will need to check the master cylinder for leaks.

    2

    Examine the master cylinder closely. The master cylinder is the metal part attached to the brake fluid reservoir in most cars. Look carefully at any tubes or hoses for signs of fluid leaking out. If your master cylinder appears moist or is dripping, it is leaking.

    3

    Crawl under your car, and look for leaks directly underneath your master cylinder. If there is a puddle of brake fluid under the car, corresponding with the master cylinder's approximate location, your master cylinder is leaking. If there are brake fluid puddles under your car that do not correspond with the master cylinder's location, you may have a bad brake line or wheel cylinder that needs to be replaced.

    4

    Get into your car, and press down on the brakes to check for pressure. The master cylinder controls your car's hydraulic braking system and maintains fluid pressure. If your brakes feel squishy, soft or mushy and you cannot find a leak or are not low on brake fluid, your master cylinder has probably stopped working.

Minggu, 06 November 2011

How to Troubleshoot a 2002 Pontiac Sunfire

How to Troubleshoot a 2002 Pontiac Sunfire

The Sunfire is a compact car which was manufactured by Pontiac but its production run ended following the 2005 model year. Typical issues with the 2002 Sunfire lie within the turn signal switch, power window motor, transmission cooler line and front brake rotors. These are the primary areas to examine when diagnosing any issues that may be affecting the Sunfire's performance.

Instructions

    1

    Check both turn signals to ensure they are functioning. Failure of one or both signals most likely indicates a faulty turn signal switch, which is located in the steering column. This will need to be replaced.

    2

    Check all power windows. Slow or non-moving windows likely indicate a faulty window motor that will need to be replaced.

    3

    Check beneath the vehicle for leaking transmission fluid. This is most likely emanating from the rubber area of the transmission cooler line. To ensure complete resolution of this issue, replacing the entire cooler line is recommended.

    4

    Check for throbbing or pulsing sensations when braking. This is likely due to worn-down front rotors that need replacing.

    5

    Ensure that the gas cap is tightly fastened. A loose cap will illuminate the check engine light.

Jumat, 04 November 2011

My 2005 Ford Taurus Is Having Problems Starting

People rely heavily on their car's performance and take comfort in knowing that when they leave for work in the morning the car will start. This, however, is not always the case and cars are notorious for failing to start when we least expect it. Regular servicing and maintenance can prevent this problem to a large degree, but wear and tear will eventually break some part of your car, preventing it from starting.

Instructions

    1

    Open the hood and use the arm lever to secure it. If your Taurus failed to start, the first component you should check is the battery. Check the battery terminals for heavy corrosion. Loosen the terminals with the small wrench and remove the negative terminal first. Wipe the terminal and clean the battery post and replace.

    2

    Check if the battery has discharged. Attempting to start the car will result in a whining noise as the engine tries to turn over but the battery lacks power. If this is the case, recharge the battery or use jumper cables and another vehicle to jump start the car. If the battery has run down owing to a faulty alternator your battery will not hold a charge and both items will need replacing.

    3

    Check your spark plugs. A faulty or cracked spark plug will fail to spark. Also, the gaps in the plugs can deteriorate due to rusting or coking (blackened surface). Pull the high tension lead from the plugs one at a time, as the leads must be kept in the correct order. Use the socket wrench to loosen the plug and remove it. Check the gap between the plug points and clean them with a wire brush. If the plug has become heavily corroded replace it as necessary.

    4

    Check the starter. Symptoms of a faulty starter will be a clicking sound when you try to start the car. The engine will not turn over if the solenoid in the starter has failed. Faulty starters will have intermittent faults and you may find that sometimes there will appear to be no problem starting but other times the clicking noise will interrupt ignition attempts. Replace the starter when this occurs.

    5

    Turn the key in the ignition and listen to the way engine responds. This can be a huge clue as to the possible problem. If your fuel injectors are blocked your engine will turn over and fire up but then, the lack of fuel in the injectors will cause the engine to stall straight away. You should see your mechanic if you do not know how to clear them.