Kamis, 30 April 2009

How to Tell if a Front Axle Joint Is Going Out?

Most cars on the road today, be they front-drive or all-wheel drive, use some kind of constant-velocity front axle joint. Cars that use them typically have four total: two on the inside of the axle shafts and another two at the ends of the axle shafts right behind the wheel hub. CV joint symptoms, regardless of make, are fairly universal; the only difficulty is in figuring out which one of the four has failed, and how badly.

Failure

    On the inside, a CV joint works something like the ball-and-socket joint in your shoulder. The primary difference is that the CV joints typically has three to six of these ball-and-sockets, while your shoulder -- presumably -- has only one. When the tiny bearings in a CV joint start to wear out, a tiny clearance opens up between the bearings and the outer bearing shell. Once that happens, the CV joint starts to build up momentum before engaging and quickly hammers the remaining bearing material into shrapnel.

Clunking Under Acceleration

    As you might expect, often times the first warning sign of impending CV joint will be the sound of the internal components hammering together. You'll notice it first as a light tap under acceleration and braking; within another hundred miles, that light tap will likely grow into a noticeable knock and then to a hard knock that you can feel through the floor. Both the inner and outer CV joints will exhibit this kind of clunking under acceleration and braking.

Clunking While Turning

    This is the classic symptom of CV joint failureand generally indicates a bad outer CV joint. The outer CV joint goes through a far greater range of motion than the inner one; about 50 to 60 degrees, compared to about 10 degrees. As such, the outer CV joint will start to pop and bind more than the inner one as its bearings flop around and wedge against each other and the bearing carriers. Generally speaking, a CV that clicks worse when turning right than it does turning left indicates a bad right-side bearing; and vice-versa for the left side. The CV will also often click worse in reverse than in drive.

Shudder and Growling

    A shuddering under acceleration may indicate a bad inner or outer CV joint. This tends to happen when the CV joint assembly bounces back and forth inside the carriers instead of clacking once and locking into place. Some vehicles are more prone to shuddering than others. A gravelly growl is usually the sound of dry metal vibrating, bouncing off of or binding on dry metal. It typically indicates a lack of lubrication, which often precedes failure in the case of a CV joint. However, growling does not, in and of itself, indicate a bad CV joint -- wheel bearings will make the same noise under the same conditions.

How to Troubleshoot Blown Spark Plugs in a '99 Ford F-250

The 1999 Ford F250 was produced in two series; the F250 and F250 Super Duty. The base engine for the 1999 F250 was a 4.6-liter V-8 engine. A 5.4-liter V-8 and 6.8-liter V-10. There are two types of ignition systems on the 1999 F250. One type uses a spark plug wire between the spark plug and the coil module. The other type uses a coil-on-plug or COP system, with a separate coil pack above each spark plug. The steps to accessing the spark plugs will vary, but the spark plug inspection procedures are the same.

Instructions

    1

    Open the hood on the F250. Disconnect the negative battery cable from the battery, using a ratchet and socket.

    2

    Remove one of the spark plug wires from a spark plug, using spark plug boot pliers to pull the wire free from the spark plug. Pull the wire off at the boot rather than the wire, because pulling the wire can damage the end of the wire attached to the spark plug. If the plug wire is attached to a coil-on-plug, or COP, remove the single mounting screw from the COP, using a ratchet and socket. Pull the coil off of the spark plug with a twisting motion.

    3

    Inspect the inner end of the wire for burn marks or excess corrosion. Inspect the entire spark plug wire from the plug to the coil pack, for cracks or damaged sheathing. If any damage is present, replace all of the spark plug wires.Remove the spark plug from the engine, using your ratchet and spark plug socket with the extension, if needed. Inspect the spark plug for damage at the outboard white ceramic end. Inspect the firing end of the plug for excess corrosion, oil buildup or white or black deposits.

    4

    Check the gap on the spark plug to make sure it is set between 0.052 and 0.056 inches. Use a gap tool to check the gap. Do not change the gap on any used platinum spark plugs. Use the chart in the "Reference" section of this article to determine the cause or causes of your damaged plug.

    5

    Perform the proper repairs on your F250 to eliminate the source of any spark plug fouling or contamination. Install new spark plugs onto the engine if you find a fouled plug during your inspection. Tighten the new spark plugs between 40 and 62 inch-pounds, using a 3/8-inch-drive torque wrench, spark plug socket and extension if needed. Install the spark plug wires by pushing them on at the boot. Install the COP by pushing it onto the plug with a slight twisting motion. Tighten the COP screw snug with your ratchet and socket.

Rabu, 29 April 2009

Low Ticking When Accelerating in a 2002 Civic

Engines are finely-tuned instruments, and Honda, in particular, prides itself on offering the finest level of tuning. But fine tuning makes for low margins of error, and tiny errors make for many symptoms that make make troubleshooting difficult. A low ticking noise can be indicative of dozens of different problems -- some of them severe and others merely annoying.

Exhaust Gasket

    Flooring the accelerator causes air and fuel to flood into your engine, after combustion, the waste gases are trying their hardest to get out. Your exhaust system and catalytic converter pose a slight restriction to exhaust gas flow, causing back-pressure to build up in the manifold and pipes. A small leak in the manifold gasket may not allow gas through under normal circumstances, but accelerating can create enough back-pressure to push it through any gap in the gasket. If that gap is right at the exhaust port of a single cylinder, as it's likely to be, escaping gases will emit a steady tick or pop that increases in frequency as engine rpms rise.

Lifter Tap

    Technically, the engines used in this generation of Civic don't have "lifters"; at best, they have hydraulic "lash adjusters" that keep the cam followers in contact with both the cams and the valves. If one or more of the lash adjusters gets gummed up with carbon or other deposits, it may stick in one position and go "solid." Solid-lifter race engines are notorious for tapping slightly under hard acceleration, because high combustion chamber pressures push back up against the valve and make it harder to control. And with no means of closing the small gaps between the valve and follower, or follower and cam, the two come together to create annoying lifter tap.

Worn Valves, Valveguides and Valveseats

    Even if your lash adjusters are working, they'll have a hard time controlling the valves if the valves, valveguides or valveseats are damaged. All of the above will cause valve tap under load for different reasons. Valveseats are the least likely if you haven't noticed a loss in power or other performance issues. Same with damaged valves, which will also likely tick at idle and under cruise conditions. Worn valveguides, however, will allow the valve to wobble around instead of going straight up and down. When cylinder pressures increase, the valves will dance around and smack against the valveguides and followers. This isn't terribly uncommon, and might not be worth the time and expense to replace the valveguides if you can tolerate the noise.

Detonation

    Your Civic uses a set of electronic "ears" to detect abnormal combustion. These knock sensors are not dissimilar in principle to the pickups on an electric guitar and perform much the same function. That is, turning sound into electrical impulses. Before knock sensors, odds would have been best that the sound you heard under acceleration was detonation; but knock sensors tell your computer when this is happening and automatically adjusts timing and fuel injection to prevent it. So, unless you experience a noticeable loss in power, a check-engine light and the appropriate malfunction codes, then detonation is extremely unlikely as a culprit. It's only worth mentioning so you don't waste your time trying to fix it.

How to Calculate AC Belt Capacity

How to Calculate AC Belt Capacity

Air conditioning belts, or V-belts, are used to drive air conditioners in motor vehicles. A V-belt derives its name from the shape of its cross-section, which looks like a V. The belts design allows its tension to improve as its load increases, making it capable of working for 25,000 hours or three years of continuous operation; since cars are not driven continuously, AC belts generally last much longer than three years. Use a simple equation to determine the horsepower that the belt is capable of handling.

Instructions

    1

    Calculate the tension coefficient of the AC belt by dividing the tight side of the belts tension (T1) by its slack side tension (T2). Use the following formula to determine an AC belts tension coefficient, where e = 2.718, k=5, f = the dynamic coefficient of friction between the belt and the sheave and = the wrap angle or arc of the contact on the belts smaller sheaves:

    T1/T2 = ekf

    2

    Factor the result of that equation into a simple formula to determine the effective tension (Te) of the belt, which you will ultimately need to calculate its capacity. Use the following equation where Sp = the AC belts stress ratings in psi and A = the cross-sectional area of the belt in inches squared:

    Te = (A) x (Sp)

    3

    Take the result of that equation, Te, and factor it into an equation that determines the horsepower that the AC belt is capable of handling. Use the following formula where V = 0.262, D = pulley diameter in inches and N = pulley speed in rpm:

    hp = (Te) x (V) x (D) x (N)/33,000

    4

    Write the horsepower figure down so that you know exactly how much horsepower your AC belt can handle, or the capacity of the AC belt.

My Dodge Cummins Won't Start Cold

My Dodge Cummins Won't Start Cold

The Dodge Cummins, like all diesel engines, needs to be heated before the engine will start correctly. If your engine is not starting when cold but starting when warm, chances are there is a problem with the heater. Follow a few steps to diagnose where the problem is and how you can fix it.

Instructions

    1

    Turn the ignition on and look for an orange light that looks like a picture of a coil. This is the indicator that the engine is being heated. Do not start the engine until this light goes out.

    2

    Open the hood and locate the grid heater that heats the engine before startup. If the engine starts without smoke or stumbling in warm weather, then this is probably the problem.

    3

    Use the voltmeter to check the wires feeding the heater for power. If there is no power, trace the wires back and see whether they are broken or grounding out on something.

    4

    Examine the terminals on the grid heater to make sure it has not burned through the terminals and there is no buildup of dirt. Clean the terminals if needed to make sure the connection is working.

    5

    Check the gap between the terminals to make sure they're not shorting out on one another. If they are, clean and change the terminals to prevent them from shorting.

    6

    Replace the grid heater if your Cummins still will not start. That will allow the engine to heat properly.

How to Test a Throttle Position Sensor With a Voltmeter

How to Test a Throttle Position Sensor With a Voltmeter

The throttle position sensor (TPS) is used by the electronic control module (ECM) to determine engine speed. When you press on the TPS, the ECM reads the TPS signal and other sensors to determine how much fuel to inject into the cylinder. The most common TPS used is the potentiometer, which outputs a variable voltage depending on the position of the throttle. If the ECM detects a problem with the throttle signal, the ECM will log a P0121 throttle diagnostic code.

Instructions

    1

    Inspect the engine harness and confirm that all connections are tight and secure. Inspect the engine harness for damage, abrasion or corrosion. To temporarily repair a broken or damaged wire, wrap the exposed wire with electrical tape. Remove corrosion with baking soda, water and a wire brush.

    2

    Locate your throttle position sensor. This may be inside the engine compartment, on the intake manifold or on the throttle pedal. Inspect the throttle wiring from the sensor to the electronic control module. Make sure the wires are free of abrasion, damage and corrosion. Inspect the linkage connections and mounting hardware. The linkage should move freely and the throttle sensor should be mounted securely to the bracket or throttle pedal.

    3

    Disconnect the throttle sensor connector. Review the schematic for the engine and locate the throttle +V and ground connection. Turn the ignition to "On." Set the voltmeter to measure voltage. Place the positive probe on the +V or +5 terminal and place the negative probe on ground. The voltage should be approximately 5 volts. If the voltage is not correct, there may be a problem with the ECM sensor supply.

    4

    Turn the ignition to "Off." Refer to the schematic and locate the throttle +V and ground connection on the ECM. Sometimes the ground connection is referred to as "Sensor Common." Set the voltmeter to measure resistance. Place the positive probe on the +V wire on the sensor connector and place the negative probe on the +V connection at the ECM. Wiggle the harness during measurement to reveal an intermittent open condition. The resistance should be less than 5 ohms. Place the positive probe on the ground wire on the sensor connector and place the negative probe on the ground or sensor common wire at the ECM. Wiggle the harness during measurement to reveal an intermittent open condition. The resistance should be less than 5 ohms. If the resistance is greater than 5 volts, there is an open circuit in the wire. Replace the wire and retest.

    5

    Refer to the schematic and locate the throttle signal on the ECM. Place the positive probe on the signal wire on the sensor connector and place the negative probe on the sensor signal wire at the ECM. Wiggle the harness during measurement to reveal an intermittent open condition. The resistance should be less than 5 ohms. If the resistance is greater than 5 volts, there is an open circuit in the wire. Replace the wire and retest.

    6

    Reconnect the throttle position sensor to the engine harness. Remove the signal wire from the ECM connector with a wire removal tool. Set a digital voltmeter to measure voltage. Place the positive probe on the signal wire and place the negative probe on ground. Vary the position of the throttle sensor. The voltage should vary from 0.5 volts to 4.5 volts. If the voltage is not correct, there is a problem with the throttle sensor. Replace the sensor and retest. If the voltage is correct, there may be a problem with the ECM. Take the vehicle to a qualified mechanic for testing and repair.

The Difference Between a Blinking & Steady Check Engine Light on a Tahoe

The Difference Between a Blinking & Steady Check Engine Light on a Tahoe

Since the early '80s, the "check engine" light has been a fixture on the dashboards of passenger cars and light trucks. It is a source of curiosity for many drivers, who have different opinions about what it means when the amber-colored engine-shaped icon lights up in their vehicle. The "check engine" light in a Chevrolet Tahoe can mean many different things, depending on whether it is flashing or steady.

Background

    The vehicle "check engine" light serves as a primary indicator of a problem with the vehicle's electronic control systems. At one time, the "check engine" light was an indicator of problems primarily affecting a vehicle's emission control systems. As automotive technology evolved, the use of electronic controls in vehicles has increased, and a "check engine" light may now indicate problems with many different areas affecting a vehicle's drivability and operation.

Flashing Light

    A flashing "check engine" light on a Tahoe indicates that the computer system has detected a misfire in the ignition system. A misfire is also known as a "skip" and occurs when at least one engine cylinder fails to ignite the fuel and air mixture as expected with normal operation. The misfire can be caused by a problem with the ignition system, or when the fuel system fails to deliver a flammable mixture of fuel and air to the cylinder to be ignited.

Steady Light

    A steady "check engine" light means that one of the sensors in the vehicle responsible for the correct operation of the engine or other vehicle systems is delivering either no data to the vehicle's computer system, or that the data is outside the normal range that the engine computer expects. Many factors can cause this, such as broken wires or failed parts.

Systems Affected

    The "check engine" light may also indicate problems with vehicle systems other than the engine and related electronics. Transmissions contain a significant number of electronic controls, and transmission problems can also turn on a "check engine" light, as can all-wheel- or four-wheel-drive systems. In some vehicles, the climate control or other comfort and convenience features can cause a "check engine" light to come on as well.

What You Should Do?

    Vehicle computers can often detect problems with electronic systems long before you may notice the problem with vehicle operation. However, the concern often grows worse over time. If your "check engine" light is on steady, check to be sure that your gas cap is tight. If it stays on, you should take the vehicle in for diagnosis and repair as soon as possible, but your vehicle is generally safe to drive. If the "check engine" light is flashing due to misfire, you should stop driving the vehicle, and have it towed in for service. Continuing to operate with a misfire can cause damage to the vehicle, particularly with the catalytic converter, that can be very expensive to repair.

Senin, 27 April 2009

Trouble Codes for the 1996 Dodge 3500 Ram Van Engine

Trouble Codes for the 1996 Dodge 3500 Ram Van Engine

The 1996 Dodge Ram Van is a large, cargo-style van with over 207 cubic feet of storage space and room for eight passengers. The Ram comes standard with a 35 gallon fuel tank, 175 horsepower and a top towing capacity of 3,500 lbs. If you've noticed a lack of power, engine trouble or the "Check Engine" light coming on in your van, it's time to scan the Dodge's computer for stored fault codes. These codes are created when the engine recognizes a problem and are your go-to source for pinpointing the trouble.

Instructions

    1

    Look under the driver's side dash of the Dodge for the Assembly Line Diagnostic Link (ALDL), also known as the diagnostic test port. The link is a small, rectangular electrical device with 12 to 16 ports. Remove the cover if it has one.

    2

    Plug the test lead of your diagnostic scanner into the ALDL port. Turn the ignition key "On," so that the dash panel instruments come on but the engine isn't cranked. This initiates the diagnostic sequence in the Dodge's computer.

    3

    Turn on the scanner. Follow the prompts on the scanner's screen, answering each question it asks. When the scanner accesses the codes stored in the engine's computer, each one will appear on the screen. Write them down so you can look up the meanings in a repair manual or online.

    4

    Address the issue behind the trouble codes, then repeat the procedure for obtaining the trouble codes. After the codes run--as they will, even if the trouble has been fixed--choose the option to reset the codes.

Problems With Low-Intensity Daylight Running Lights

Problems With Low-Intensity Daylight Running Lights

Low-intensity daytime running lights are designed to make vehicles easier to see. Daytime running lights were first introduced in northern countries and areas where it is dark for longer periods of time, such as Canada and Scandinavia. Daytime running lights have been reported as making the roadways safer, because vehicles that are equipped with them are more noticeable than those without. However, there have been some documented complaints and problems associated with using these lights.

Fuel Consumption

    Daytime running lights, like all electronic equipment in your car, are powered by your engine and its electrical charging system. The energy that is being used to power the lights reduces the amount of energy available for your engine. This causes your engine to have to work slightly harder, causing a reduction in your vehicle's overall fuel economy. This also causes an increase in vehicle emissions. While this is a mild problem for a single car, the combined effect of thousands of cars with daytime running lights adds to the overall pollution and use of limited natural resources.

Distracting

    Daytime running lights have a tendency to increase visual glare. The more lights that are on a road, even low intensity lights, the more lights each driver has to deal with. While daytime running lights may make the occupants in vehicles that are equipped with the lights safer, the lights may be distracting for other drivers by drawing attention away from or obscure people or objects that are not equipped with daytime running lights, such as pedestrians, bicyclists, other vehicles and road hazards.

Reduce Signaling Effectiveness

    The National Motorists Association reports that daytime running lights reduce the effective visibility of directional signals, such as turn signals and hazard lights. With one light on consistently, other drivers are more likely to have a hard time spotting a blinking light that is next to or underneath the daytime running light.

How to Test an Ignition Control Module

How to Test an Ignition Control Module

The electronic ignition control module is a solid state "On/Off" switch for the ignition system. The module receives a signal from a sensor inside the distributor. The signal is then used to fire the ignition coil creating the energy for the spark plugs. The ignition module may be located inside the distributor, on the distributor housing, or mounted to the side of the engine compartment. When a module goes bad, it normally fails totally and the engine won't run at all. Checking your ignition module is an easy task that requires only the simplest of tools.

Instructions

    1

    Remove one plug wire at the spark plug and insert an old spark plug into the end of the plug boot. Place the spark plug on a metal surface on the engine. Crank the engine and check for a spark at the old spark plug. No spark on the plug indicates an ignition problem.

    2

    Check for voltage at the coil positive terminal when the ignition key is on. Place the red lead of the multimeter on the positive coil terminal. Place the black lead to the battery negative terminal. Turn on the ignition switch to the "Run" position. The multimeter should read battery voltage at the positive terminal. If voltage is not present, then the problem is with the ignition switch or ignition wiring circuit.

    3

    Locate the ignition module positive (+) wire. Turn the key "Run" position without starting the engine. Pierce the positive wire with the multimeter's red lead. There should be a reading of battery voltage at the wire. If battery voltage is not present, check for an open circuit between the wire and the ignition switch.

    4

    Locate the ignition module negative (-) wire. Pierce the negative wire with the multimeter's red lead. Remove the distributor cap without removing the spark plug wires. Rotate the distributor center shaft by hand or by cranking the engine. Observe the distributor rotor as the engine is being cranked over. If the distributor rotor fails to turn, then the distributor or distributor gears are bad. The multimeter should read voltage alternating between battery voltage and zero.

    5

    Replace the ignition module if the multimeter reading fails to fluctuate between battery voltage and zero as the distributor is turning. Install the distributor cap and fasten it securely to the distributor. Disconnect the multimeter from the ignition module and battery.

Minggu, 26 April 2009

My Ford Has TorqShift Transmission Problems

My Ford Has TorqShift Transmission Problems

Ford built the new 6R140 to work in the F-Series Super Duty's 6.7L diesel and 6.2L gasoline engines; prior to 2005, the TorqShift was only available with the Power Stroke diesel engine. There are not any major issues reported yet for the 6R140; however, the previous version of the TorqShift had some problems.

Intermittent clucking sound

    Hearing an intermittent clunking sound when shifting from drive or reverse to park, from reverse to drive or at the 2-3 upshift is normal play in the drivetrain.

2005 Models Stall When Engaging Drive or Reverse or at Stops

    Trucks built between October 1 and November 30, 2004 may stall due to a sticking torque converter control solenoid. To resolve this, the transmission pan needs to be cleaned, the cooler flushed and the solenoid and external fluid filter replaced.

Harsh or Delayed Forward or Reverse Engagement

    This problem caused a recall of 2004 trucks and some repairs required the entire solenoid body to be replaced.

TorqShift PTO Failure

    Trucks may exhibit low or no torque due to PTO failure or low line pressure. The PTO needs to be reprogrammed to the latest calibration to fix a line pressure problem and the transmission should be inspected for damage. A PTO failure is likely due to incomplete PTO wiring.

Squealing Noises on a Ford Taurus

Squealing Noises on a Ford Taurus

Squealing sounds in a Taurus are caused by moving parts rubbing together. Metal in contact with either metal, rubber or ceramic can make squeals. These parts are either rubbing or spinning. Examples include bearings, struts, belts and brakes. A squeal may indicate serious problems, but many are maintenance issues or minor annoyances. Certain driving conditions may also create temporary squeals. You can pinpoint the source of most squeals with a little persistence and an understanding of contact points.

Instructions

Outside Squeals

    1

    Shine a flashlight through the front wheel slots. The brake rotor is a polished metal disc behind the wheel. Run your finger over the rotor. Deep grooves or a warped feeling indicate you need a brake job. Intermittent squealing or a high squeak when applying brakes is common. Check with your mechanic about anti-squeak brake pads. Consistent brake grinding or pedal vibration is not normal.

    2

    Get your shocks and struts inspected if you notice excessive squeaking or squealing when going over bumps. They could be worn, or bolts may be loose. Have the strut towers checked.

    3

    Check your wiper blades if they squeal when the windshield is wet. A retainer clip may be loose. If the wiper is touching the glass, fix it immediately. It's like fingers on a chalkboard, and it will damage the windshield. A squealing wiper on a dry windshield does not indicate a problem.

Under the Hood

    4

    Open the hood, and check the power-steering-fluid reservoir, located just behind the radiator on the passenger's side of the engine. If it's very low, the bearing may be squealing. Fill the unit to the proper level.

    5

    Examine the drive belt. Check for oil or water leaks, which may spill onto the belt and cause it to slip. Use a flashlight to inspect the back side of the belt for wear. Look for deep cracks in the ribbed areas. The Taurus Owner's Manual recommends replacing the drive belt every 30,000 miles.

    6

    Wear work gloves, and find the drive belt tensioner, which is a pulley about 3 inches in diameter attached to a spring-loaded lever. The drive belt runs over the pulley. Grasp the pulley, and try to wiggle it. Push on the belt to check the tightness. It should not move more than an inch. Replace the tensioner if it is loose, has excessive play or if metal shavings are seen nearby.

    Start the engine and leave the A/C off. Shine a flashlight on the tensioner pulley and watch it. Replace the pulley if it constantly moves back and forth, wobbles or squeals. Listen closely since noisy belts are more common than a malfunctioning tensioner.

    7

    Turn on the air conditioning and listen for any changes. An early sign of compressor failure is a sudden squeal when it is engaged. It can also be a sign of a weak tensioner.

Inside Squeals

    8

    Leave the engine running, turn the fan on low and then gradually increase the blower speed. Persistent squealing is a sign that the blower motor bearings may be failing and need to be replaced. However, moisture or dust can get into the unit, making it squeal intermittently without a mechanical failure.

    9

    Turn the steering wheel completely to the left. Wait 5 seconds, then turn it completely to the right. A screeching or squealing sound is normal here. The power steering relief valve is bleeding off excess pressure. Squealing while turning points to a drive belt issue that needs to be looked at by a mechanic.

    10

    Listen for noises coming from the Taurus steering column while turning the wheel. It means the bushings are dry or worn. This is not a major concern, although it can be irritating.

    11

    Roll the windows down and back up. Treat the rubber seals with vinyl protectant if they're squealing. Lubricate noisy door hinges with oil or a spray lubricant.

How to Check for a Bad Thermostat

How to Check for a Bad Thermostat

A thermostat is an essential component of the engine's cooling system. The thermostat's function is to maintain the temperature of the coolant in the vehicle, keeping it within the normal operating range. When the thermostat is in working condition, it will open when the temperature of the engine reaches its normal range. The coolant will then circulate through the radiator, where it will cool down. When the thermostat becomes defective, it will not open properly. Checking for a bad thermostat can be done using a simple technique.

Instructions

    1

    Open the hood of the vehicle and secure it in place. Make sure that the vehicle's engine is completely cool. Locate the thermostat, found underneath the radiator cap. You will see a short black hose that is attached to the thermostat. Place a container underneath the vehicle to catch the coolant from the hose.

    2

    Loosen and remove the screws that are located on either side of the hose, then twist the hose until it becomes loose. Remove the screws from the thermostat cover, then remove the cover along with the thermostat.

    3

    Heat one quart of water in a pot to 200 degrees Fahrenheit. Use a cooking thermometer to test the temperature of the water. Place the cooking thermometer into the water and watch the gauge, while the water starts to heat.

    4

    Place the the thermostat gently into the pot of hot water when it reaches 200 degrees Fahrenheit. A cooking thong can be used to submerge it into the hot water to prevent splashing. If the thermostat is working correctly, it should start to open up immediately. If it still remains closed, that means that your thermostat is bad and needs to be replaced.

Sabtu, 25 April 2009

How Do You Tell If the Vacuum Switching Valve on a 1998 Toyota Camry Is Bad?

How Do You Tell If the Vacuum Switching Valve on a 1998 Toyota Camry Is Bad?

The vacuum switching valve (VSV) is a part of the exhaust gas recirculation (EGR) system of the 1998 Toyota Camry. The VSV is connected to the EGR valve. The function of the EGR system is to recirculate exhaust gases to the intake manifold of the engine and thereby reduce the nitrous oxide emissions of the vehicle (References 1). Detecting a bad VSV is difficult, but can be accomplished after completing a few tests.

Instructions

    1

    Locate the vacuum switching valve. It has three vacuum hoses and a two-wire electrical connector attached to it. On four-cylinder engines, the VSV is located on the rear of the engine below the intake manifold. On six-cylinder engines, the VSV is under the V-Bank cover (a plate with fins), which must be unbolted using an Allen wrench, and then removed by lifting it off its retaining clips. The VSV is next to the intake manifold.

    2

    Check the resistance. Remove the electrical connector from the VSV and check the resistance across the terminals using an ohmmeter. The resistance should be 33 to 39 ohms (at an air temperature of 68 degrees). Resistance outside this range indicates that the VSV is bad (References 1).

    3

    Continuity test. Verify, using the ohmmeter, that there is no continuity between either VSV terminal and an electrical ground on the engine. Any continuity at either terminal indicates the VSV is bad.

    4

    Blow test. Remove the vacuum hoses from ports E and G. Blow air into port E and check that it comes out at port G. If it does not, the VSV is bad.

    5

    Apply voltage and blow air. Apply battery voltage across the VSV terminals using wires from the battery terminals. Blow air into port E and see if it comes out of port F. If it does not, the VSV is bad (References 1).

How to Diagnose a 5.2L High RPM Misfire

How to Diagnose a 5.2L High RPM Misfire

The Chrysler 5.2L engine has been the primary V8 engine used in many Dodge and Chrysler cars since the early 1970s. It was revised into the Magnum 5.2L block in 1992 which, like most modern cars, relied on more electrical peripheral components such as an on-board diagnostics system and real-time, engine-timing tuning. However, the addition of electrical systems also makes diagnoses of misfires more challenging due to the increase in peripheral systems controlling a cylinder's air, fuel and spark.

Instructions

    1

    Attach a diagnostics scanner to your vehicle's on-board diagnostics system. Turn the car to "Accessory" and enter the scan mode of the scanner. Write down any codes and look specifically for those signaling a misfire in a cylinder if the vehicle is older than 1995. For all vehicles 1992 or later, compare oxygen and air-to-fuel ratios with those in your vehicle's repair manual once the engine is at running temperature. High air-to-fuel ratios and skewed oxygen readings indicate improper burning or fuel delivery problems.

    2

    Remove each spark plug from the engine with a socket and inspect for cracking, fouled or burned plugs. If the misfiring cylinder is known, check for black or brown buildup and use a spark plug color chart to help determine whether the cylinder is lacking fuel or spark.

    3

    Replace all spark plugs. Coat each thread with anti-seize compound to avoid stuck spark plugs which can break off during subsequent removals.

    4

    Inspect spark plug and coil wires for cracking or exposed metal. These change the resistance properties of the wires, causing misfiring at high RPMs. If damage is evident, replace all the wires to maintain uniform resistance to all cylinders.

    5

    Attach a fuel-pressure gauge on the incoming fuel lines of the engine. Tape the gauge to the front window glass and drive at wide-open throttle while monitoring the fuel gauge. Check the vehicle repair manual for minimum fuel pressure at wide-open throttle and compare the vehicle's performance with it. If fuel pressure drops below the recommended level, check the fuel-pressure regulator and fuel pump for failure.

    6

    Check timing while driving using the diagnostic scanner. Ensure timing is automatically advanced at high RPMs and listen for high-pitched pinging in the engine which can cause misfires. Adjust the timing as needed to ensure spark is appropriately delivered to the cylinders.

    7

    Use a multimeter to test the fuel injectors' resistance where the injector harness attaches to the injector clip. Compare the values found with the recommended value from the injectors' manufacturer and replace as necessary.

    8

    Remove the fuel rail with injectors still attached and unplug the coil wire to prevent fuel ignition. Turn the engine over while observing for proper spray pattern. Replace or professionally clean any injector which is partially clogged and reinstall the fuel rail to complete the diagnosis.

Jumat, 24 April 2009

How to Reset Fuel Switch on a 2002 Ford F150

The 2002 Ford F-150 is a full-size pickup truck, available with several different cab configurations and bed sizes. Base models received a 4.2-liter V6 engine, while upgraded trim packages utilize either a 4.6-liter or 5.4-liter V8. The 2002 model year features a fuel pump cut-off switch designed to inhibit the delivery of fuel to the engine if an accident occurs. The fuel pump cut-off switch also has the potential to disengage the fuel pump after a hard jolt, preventing the engine from running.

Instructions

    1

    Switch the ignition to the "OFF" position and examine the underside of the truck or fuel leaks. Open the vehicle's hood and check the engine compartment for fuel odors/leakage, as well.

    2

    Reset the fuel pump cut-off switch by pressing the small, round button, located near the passenger-side kick panel, underneath the right-side portion of the glove compartment.

    3

    Switch the ignition to the "ON" position. After a few seconds, switch the ignition back to the "Off" position and check your vehicle for fuel leaks. If you do not find any fuel leaks coming from the engine compartment or underneath the vehicle, resume driving the vehicle in a normal fashion.

My Turn Signals Don't Work When My Brakes Are Applied

My Turn Signals Don't Work When My Brakes Are Applied

Tail lights, turn signals, hazard lights and brakes use separate bulbs but often are powered by similar fuses, relays and wiring.

Bulbs

    A burned-out bulb can cause a malfunction.
    A burned-out bulb can cause a malfunction.

    Bulbs can burn out, causing the turn signal to malfunction. Check each bulb independently and replace any burned-out bulbs.

Fuses

    Bad fuses can cause vehicle lights to stop working.
    Bad fuses can cause vehicle lights to stop working.

    Fuses can go bad, causing one of your vehicle's lights to malfunction. Ensure that your fuses are functioning by checking each light individually. If one does not light, change the fuse that corresponds with that light.

Wiring

    Corroded wiring causes shorts in the electrical system.
    Corroded wiring causes shorts in the electrical system.

    The wiring to your lights can become corroded, causing the lights to malfunction. Check the wiring to each light and look for corrosion. If two wires are corroded and are touching, one will cancel the other when in use; in this case, the brake would override the turn signal. The wiring will need to be replaced.

Relay

    The relay for the blinker, which works the hazards and turn signals, can go bad, causing a solid light rather than a blinking light. Replace the relay.

How Do I Troubleshoot the Temperature Cooling System in a 2001 Nissan Altima?

How Do I Troubleshoot the Temperature Cooling System in a 2001 Nissan Altima?

The 2001 Nissan Altima's engine was filled at the factory with antifreeze/coolant to provide anti-freezing protection in the winter and overheating protection in the summer, according to the Nissan owner's manual. The coolant product includes rust and anti-corrosion inhibitors. A coolant temperature gauge is provided on the dashboard to help with troubleshooting the engine cooling system. Problems with the cooling system can include the car overheating.

Instructions

    1

    Monitor the coolant temperature gauge on the dash if you suspect the Altima might be overheating. The gauge indicates whether the coolant is within the normal range or has overheated. If the gauge registers between the "C" and "H" gradations, the engine is operating within safe limits and no action is required. Be aware that the temperature gauge can read high on warm summer days, but the engine is not overheating unless the gauge needle goes into the gradation above "H."

    2

    Add coolant to the opaque, plastic coolant reservoir if the fluid level is low and the engine has been overheating. Allow the engine to cool down first by parking in the shade and shutting off the engine. Check the coolant level in the reservoir. It should be between the "Min" and "Max" levels. If it's at or below "Min," add coolant to the "Max" level by flipping open the lid and carefully pouring it in. Do not spill coolant on the ground as it is toxic and poses an environmental hazard.

    3

    Add coolant to the radiator, too, if the plastic reservoir was completely empty. Check the radiator when the engine is cold by unscrewing the cap at the top and looking in. If the fluid level is low, add coolant to the radiator.

Kamis, 23 April 2009

How to Troubleshoot a 1995 Oldsmobile Aurora Fuel System

How to Troubleshoot a 1995 Oldsmobile Aurora Fuel System

A 1995 Oldsmobile Aurora's engine, fuel system and emissions are all covered by the same first generation on-board diagnostic system. The Aurora's electronic control module interacts with sensors in each of the three areas. The ECM identifies and records malfunctions as they present themselves. Accessing this record can lead you a list of known problems, which can greatly speed up troubleshooting the Aurora's fuel system. This is, however, only the starting point. Eventually, you will have to investigate by hand.

Instructions

    1

    Compile a set of resources by locating a list of General Motor's flash fault codes. You will not find them within the Oldsmobile Aurora's owner's manual. These codes can be printed off a website (see Resources), or you can consult a Haynes manual for this model of Oldsmobile.

    2

    Sit behind the Aurora's steering wheel and place the printed out flash fault codes in the navigator's seat. Look under the Aurora's steering column. You will found the automobile's assembly line data link, which is a hub of 12 pin-receiving slots.

    3

    Find the "A" and "B" slots on the ALDL. Both are in the top row, side by side, and next to each other. Place one end of a jumper wire into the "A" slot. Place the other into the "B."

    4

    Turn the Aurora's electrical system on. However, leave the engine off. Pick up a pen and a notepad.

    5

    Count how many times the check engine light flashes. These lights will be in a coded sequence of long and short flashes. The first flash is the longest,and the second is the shortest. For instance, General Motors "code 12" will be one flash followed by two flashes. All General Motors codes are made up of two numbers. After the second code is conveyed, there will be a pause before a new fault code sequence begins. Jot each code set down.

    6

    Consult the resources you collected in Step 1. Look up each code number and its corresponding definition. At the beginning of the entire process, you will see "code 12." You can safely ignore it. "Code 12" always begins the whole self-testing procedure.

    7

    Turn the Aurora's electrical system off. Pull the jumper wire from the ALDL's "A" and "B" slots. Open the hood, and troubleshoot the codes on the list. For example, "code 54" refers to a failure in an Exhaust Gas Redirection (EGR) circuit. "Code 36" refers to an error in the ignition system circuit. For every code you copied down, investigate not just the circuits or components referred to. Check the entire system around the circuit or component.

ECM Problems in the 1995 Pontiac Grand Am

ECM Problems in the 1995 Pontiac Grand Am

The 1995 Pontiac Grand Am has one recall for electrical problems and several technical service bulletins (TSB) concerning electronic control module (ECM) problems. The ECM is the computer of the Grand Am and controls all the electronics and most of the operations of the Pontiac. Several different symptoms are created when the ECM is having a problem.

Starter Problems

    The 1995 Pontiac Grand Am has a recall on the automobile because the starter tends to burn out. Once the starter has failed, the Grand Am owner will hear a clicking sound when the ignition key is engaged. The starter problem is attributed to an ECM problem. The ECM allows too much voltage into the starter solenoid causing the starter electrical connection to melt. The melting connections can also create a fire hazard. The starter and solenoid need to be replaced as well as the ECM requires reprogramming to ensure this problem does not happen again.

Rough or Prolonged Starts

    A TSB is published by the manufacturer on the 1995 Pontiac Grand Am about rough or prolonged starting problems. This starting problem is attributed to a faulty ECM in the Grand Am. The ECM controls and monitors the fuel injectors, distributor and fuel injector system as well as other major starting components. When the ECM is failing or programmed incorrectly , the Grand Am engine has problems starting. The TSB states that the fuel injectors are not providing the cylinders enough fuel to ignite the engine and the ECM is the component which controls this starting function.

Engine Misfire

    The 1995 Grand Am has a TSB published on the Pontiac about excessive engine misfire problems. The ECM controls the distributor and coils which times the engine's cylinders. Once the timing of the cylinders firing is not being controlled properly, the Grand Am begins to misfire or backfire during start-up and acceleration. This misfiring problem can damage the distributor, coil, spark plugs and cylinder heads if the ECM problem is not corrected immediately. When the vehicle misfires, too much fuel is being injected into the cylinders, the cylinders are not being fired in the correct order or cylinder firing is being missed completely.

Rabu, 22 April 2009

How to Troubleshoot a 1984 Quadrajet

How to Troubleshoot a 1984 Quadrajet

Performance problems with carburetors can be caused by a number of issues. Ignition timing and distributor performance faults can have effects on engine performance that seem fuel related. Pressure and volume delivered by the fuel pump must meet specifications for the carburetor to be able to produce the correct air/fuel mixture under all conditions. Defective charcoal canister control valves will seriously affect performance of a perfectly good Quadrajet. Correct installation of a clean fuel filter is critical on a Quadrajet to prevent overfill of the float bowl or fuel starvation at higher RPMs. Address these items before condemning carburetor performance.

Instructions

    1
    After-market air filter housings often have no snorkel, snorkel hose or vacuum fittings.
    After-market air filter housings often have no snorkel, snorkel hose or vacuum fittings.

    Remove the air filter housing snorkel hose completely and set it aside. Remove the wing nut and lid. Lift the housing up and disconnect the vacuum hose attached to the underside of the housing.

    Plug the vacuum hose at the housing end. You can use golf tees to plug almost any size vacuum hose.

    Observe choke action on a cold engine by opening the throttle with the engine off. The choke blade should respond by quickly closing almost all the way. The space left open in front of the choke blade is called an air gap. Adjust choke blade air gap to specification by increasing or decreasing choke spring tension.

    2

    Attach a tachometer according to manufacturer's instructions. Start the engine and observe the vacuum operated choke pull-off on the rear passenger side of the carburetor. The choke pull-off increases the choke blade air gap once the engine starts. Adjust this gap to specification by turning the hex head screw in the back of the pull-off, if so equipped. If no adjustment screw is present, make adjustment by slightly bending the choke pull-off linkage. Observe engine speed displayed on the tachometer. Adjust fast idle speed to specification by turning the screw that rests on a stepped cam forward of the choke pull-off.

    3

    Occasionally rev the throttle slightly as the engine warms in order to decrease engine speed. Take notice of the choke blade movement as the engine warms. Adjust or replace the choke spring if the choke blade fails to open completely on an engine that has reached operating temperature. Turn the engine off and de-energize any idle speed control solenoid present. Restart the warm engine and adjust base idle speed by turning the screw at the throttle cable pivot point on the driver side of the carburetor. Energize disabled idle speed solenoid and note idle speed. Adjust solenoid to achieve specified idle speed per application.

    4

    Turn the engine off. Look into the primary barrels of the carburetor with a flashlight. Open the throttle briskly while watching for a squirting stream of fuel in both barrels. Do not repeat this procedure more than two or three times or engine flooding may occur. Replace the accelerator pump if the stream is late or weak. Poor accelerator pump performance will cause hesitation or engine stalling upon acceleration.

    5

    Check the primary throttle shaft for bore wear by attempting to move the shaft forward and backward and up and down. Noticeable movement in any direction indicates wear that requires repair or replacement of the throttle body. Secondary throttle shaft wear or warp-age can prevent the throttle plates from closing completely. Secondary throttle plates that hang open or fail to move smoothly also require repair or replacement of the throttle body.

    6

    Fuel supply to the secondary barrels is controlled by the rear needles and jets. Adjust the rear needles according to specifications. Incomplete or late needle action will cause the engine to bog down under heavy acceleration. This condition is commonly found and is responsible for the carburetor's nick-name of "Quadra-bog." Detach the tachometer and reinstall the air filter housing completely.

How to Tell If the Power Steering Is Out

The power steering system is an important part of your vehicle. The power steering makes your vehicle easier to turn and handle, especially in hazardous conditions. Power steering has been commonplace on vehicles since the later 1960s and newer model vehicles are not designed to be driven without power steering. If you suspect your power steering system is having a problem, you are probably right. However, there are a few quick ways to verify your suspicions.

Instructions

    1

    Open your car's hood. Locate the power steering reservoir and check the power steering fluid. If the fluid is low or empty, chances are your power steering system is leaking. If your power steering pump runs out of fluid it will not work, and your car will not have power steering.

    2

    Look for broken or damaged serpentine belts or pulleys in your car's engine compartment. The power steering pump in most vehicles is powered by the accessory belt, so if the belt breaks or isn't functioning properly, your power steering is one of the systems that will stop working.

    3

    Get in your car with it turned off and attempt to turn the wheels without locking the steering wheel. Turning the wheel should be difficult due to the lack of movement and power steering.

    4

    Start your car up and try to turn the wheel left and right. If there is no change in how it feels, your car does not have power steering. Power steering will make the wheel far easier to manipulate and turn.

How to Tell When a Turn Signal Switch Is Bad

How to Tell When a Turn Signal Switch Is Bad

If your turn signal has stopped working, there are several possible reasons. You could have a bad bulb in the turn signal or in the dash indicator. Or you could have a blown fuse. Those are simple items to check first. However, if they don't solve the problem, then you either have a bad flasher or a bad turn signal switch assembly. To perform these troubleshooting steps, you'll need your vehicle's owner's manual, which contains schematics for the electrical components of the turn signal.

Instructions

    1

    Identify which turn signal bulb is not working. There are normally two on the driver's side and two on the passenger's side, at both the front and the back of the vehicle. Open the hood or trunk and unscrew the bolts attaching the bulb assembly to the frame so that you can replace the bulb that is not working. Unscrew the bulb and replace it. See your vehicle's owner's manual if you need help unbolting the bulb assembly. If this fixes the problem, stop. If not, go to Step 2.

    2

    Find the fuse box, usually under the dashboard, where the turning light signal indicator fuse is found. Remove the fuse, using needle-nosed pliers if you have a hard time gripping it with your hands. Insert the new fuse, pressing it into position with your finger. If this does not resolve the problem, continue to Step 3.

    3

    Determine how, according to the owner's manual, to access the in-dash lightbulbs if the turn signal does not display in the dash. You may need to remove a part or all of the vehicle's dashboard to access the bulbs. If the turn signal displays and flashes correctly in the dash, proceed to Step 4. If the signal is flashing too quickly or too slowly, you may have the wrong type of bulb installed. Change the turn signal bulb, using a replacement of the type listed in your owner's manual. If this does not solve the problem, proceed to Step 4.

    4

    Use the adjustable wrench to disconnect the negative battery cable from the negative battery terminal post.

    5

    Use the Phillips or flathead screwdriver to remove the cover from around the area of the steering column where the turn signal flasher and turn signal assembly are located.

    6

    Unplug the flasher. Note that there are three prongs, two vertical and one horizontal. Apply one test wire to the horizontal prong and one to a vertical prong. Listen to hear the flasher click. If it does not click, test it again using the horizontal prong and the other vertical prong. If it does not click, replace the flasher. If it clicks or if replacement does not resolve the problem, your turn signal switch is bad.

Selasa, 21 April 2009

Troubleshooting an F-150 Truck

Troubleshooting an F-150 Truck

The F-150 is a half-ton Ford truck that was introduced to the market in 1948 and although it has evolved into a modern machine, the truck was never removed from the market. The F-150 trucks manufactured prior to 1995 require basic mechanical observations for troubleshooting but the more current models require a combination of mechanical observations and an electronic computer reader to test the sensors and various engine components. The F-150 is a staple in the Ford lineup and design promotes power with better fuel economy than the larger models.

Instructions

    1

    Turn the key and attempt to start the engine. If the engine is dead and the interior lights are faltering or dead, the battery must be charged. Attach the battery to a trickle charger and leave it until it reads as being fully charged. Start the vehicle. If the battery continues to drain, replace it with a new one.

    2

    Attach a voltage meter to the alternator if the battery is good but the power continues to fail. If the alternator is not putting out electric current, it must be replaced. If the alternator is good, use a screwdriver to simultaneously touch the alternator and the nearest piece of metal -- for 1980s models. If the engine starts, the linkage in the ignition assembly must be replaced.

    3

    Replace the spark plugs and clean the carburetor or fuel injection system if the engine cranks but does not start. Spray the carburetor with a commercial cleaner and attempt to start the vehicle. If the problem is not fixed, the carburetor requires tweaking. The injector tips and hoses may require replacement on fuel injection models.

    4

    Drive the vehicle on an uncrowded road. If the engine sputters and the power surges, the truck may require a new fuel pump. If it is difficult to steer, the power steering pump may be bad. Difficulty steering on a flat surface is also attributed to locked hubs on four wheel-drive models.

    5

    Rapidly accelerate and decelerate to test the transmission. If the transmission stalls, grinds, pops or jolts, it must be serviced. The transmission is extremely important and you must have it serviced immediately.

How to Troubleshoot a Radio on a 2001 Oldsmobile Alero

How to Troubleshoot a Radio on a 2001 Oldsmobile Alero

The 2001 Oldsmobile Alero from General Motors was sold with radio options that included AM-FM stereo with cassette and CD. No satellite or auxiliary MP3 music player input option was offered. One distinctive feature provided on the 2001 Alero was a "Personal Choice Radio Controls" option that can recall the most recent radio settings used by a specific driver. The car also came equipped with a theft-deterrent system. Most problems with the radio on the 2001 Alero can be corrected through troubleshooting.

Instructions

    1

    Use the "Unlock" button on one particular radio transmitter key fob to unlock the vehicle if you want the radio to remember your personal settings. The system works by tying in particular settings to the last transmitter that was used to open the car. If you use a different fob, your settings won't be loaded.

    2

    Turn the radio and vehicle off to activate the anti-theft feature if the red security light doesn't flash. This option won't work when the Alero is running. The feature works by memorizing part of the Vehicle Identification Number (VIN) and disabling itself if it is move to an unrecognized car. Look for a blinking red light that indicates the Theftlock feature is activated.

    3

    Press the "SCV" button if road noise degrades the radio sound. SCV stands for "speed compensated volume" and this option allows you to compensate for road noise on the Oldsmobile Alero radio. Choose between "Min," Med" and "Max" settings.

    4

    Inspect the rear window for broken or damaged wiring elements if the radio range is poor. The radio antenna on the 2001 Alero is embedded in the rear window and is susceptible to damaged. Have the antenna replaced if visible signs of damage are apparent.

Jeep Liberty Oil Problems

Jeep Liberty Oil Problems

The Jeep Liberty is designed to use 10W-30 API motor oil when operating in normal temperature ranges. Oil and filter changes are recommended every 3,000 miles. When this schedule is not followed, engine problems may occur.

Dark Oil or Sludge

    When the Jeep Liberty oil has not been changed in a long time or after heavy use, the oil filter stops filtering debris from the oil and it becomes dark with particles. These particles cause wear on engine parts. In extreme cases, the oil becomes sludge and clogs oil passages.

Milky or Watery Oil

    Water drops in oil or milky oil is a symptom of a potentially more serious engine problem. A blown cylinder gasket, cracked cylinder head or engine block is allowing water to leak into the oil system. The engine needs to be checked as soon as possible.

Low Oil Levels

    Low oil levels are a symptom of an oil leak. A leaky seal, broken gasket or worn piston rings or valve guides all could be the cause. If the piston rings are worn, the low oil levels may be accompanied by smoky exhaust.

Senin, 20 April 2009

How to Know When to Replace Your Hub Bearing

How to Know When to Replace Your Hub Bearing

The wheel bearings in your vehicle allow the wheels to rotate freely around the axle or spindle. Wear, noise and damage usually are clear indicators that you need to replace the wheel bearings in your vehicle. However, some cars use sealed units that may be tricky to diagnose. Still, there is a way for you to check these bearings at home, using a few simple tools and tricks so that you know when to replace your hub bearing, and save money in unnecessary repairs.

Instructions

    1

    Raise the wheel with the hub bearing you need to check off the ground using a floor jack and support it with a jack stand under the frame.

    2

    Grab the front and rear of the tire with your hands and try to move the tire in and out. If you notice some play on the wheel, you need to replace the wheel bearing.

    3

    Rotate the tire with your hand as you listen to the hub bearing with a mechanic's stethoscope. Place the tip of the stethoscope against the center of the wheel. If you hear a soft or loud grinding noise as you rotate the wheel, you need to replace the hub bearing.

    4

    Remove the wheel assembly and drum, if you are checking a rear hub bearing and you have a drum brake assembly installed. Use a lug wrench to remove the tire, a pair of needle-nose pliers to remove the cotter pin securing the axle nut on the center of the wheel hub and an axle socket and ratchet to remove the axle nut on the center of the wheel hub.

    5

    Remove the brake drum, and the outer and inner wheel bearing from the brake drum.

    6

    Check visually the outer and inner bearings and the races where the bearings ride inside the drum. Inspect the components for pitting, rust, cracks and worn out spots. If you notice any damage or wear, replace them.

Is There Only One Fuse Box in a Fiat Punto?

The fuse box of the Fiat Punto is a control center for many electrical functions of the vehicle. Knowing the location of the fuse box should make troubleshooting and fuse replacement simpler tasks.

Number of Fuse Boxes

    Most late model Fiat Puntos have one fuse box, but some sporting editions may have two. Consult the owner's manual to determine if there are one or two fuse boxes in your specific model.

Location of Interior Fuse Box

    The interior fuse box is located to the right of the steering column. There are two screws in the dashboard that must be loosened with a screwdriver in order to fold down the cover to access the fuses. A diagram on the inside of the flap delineates the purpose of each fuse.

Location of Exterior Fuse Box

    In models with two fuse boxes, the second fuse box will be located under the hood. The fuse box is to the right-hand side of the compartment and has a black plastic cover that must be removed to access the fuses inside.

My 1997 Altima Won't Start

My 1997 Altima Won't Start

When your 1997 Altima won't start, there could be a number of reasons why. Many factors must come together for an engine to successfully start. The energy flow sends a spark from the battery into the electrical components of your engine. The air flow pulls in air, filters particles from it and mixes the clean air with fuel in the carburetor or fuel injection system to trigger the small charge that forces the engine to start. The fuel flow pulls in the gas, filters impurities from it, and sends it to the right component.

Instructions

    1
    Check the spark plugs, wires and battery to make sure the energy flow is working.
    Check the spark plugs, wires and battery to make sure the energy flow is working.

    Check the energy flow. Start with checking the battery. If your headlights, radio and interior lighting is coming on, chances are, the battery is fine. Inspect the wiring for the spark plugs for splits and rotting. Remove one of the spark plug wires by just pulling the wire off of the distributor. Have someone turn the ignition key slightly while you are watching inside the wire for the spark. If there is a spark, the energy flow is at least getting to the distributor. If there is not a spark, there could be a problem with the ignition or the distributor assembly. Check the spark plugs for wear or for broken ends. If the spark is transferred from the battery to a bad spark plug, or plugs, it could lead to the engine "missing" or not starting at all.

    2

    Check the air flow. Open the hood of the vehicle and remove the air filter which will be located on the right side near the brake fluid reservoir. Remove any debris that may be blocking the vents and inspect the condition of the air filter. If it is clogged with dirt, the air is not getting to the air-fuel mixture chamber and will prevent the Altima from starting. Replace air filter and try starting the Altima again.

    3
    Fuel flow is just one problem that could keep the Altima from starting.
    Fuel flow is just one problem that could keep the Altima from starting.

    Check the level of fuel. You may simply be out of gas. Check the fuel filter. It is located on the driver's side in the rear of the engine compartment. Remove the fuel pump fuse from the interior fuse box in the dashboard. Start your engine, this will drain the remaining gas from the fuel lines to minimize the amount of gas spillage when you replace the fuel filter. Unclip the fuel filter and remove the gas lines with a slight pull. If there is sludge or blockage it will be easy to see. Replace the fuel filter and the fuel pump fuse and try starting the vehicle again.

    It's possible that the fuel pump itself is not working which will also prevent the Altima from starting. Some auto parts stores will have a vehicle diagnostic tool which will let you know which part of the fuel flow or other system is failing.

    4
    The Wheel Lock could be what is preventing your vehicle from starting.
    The Wheel Lock could be what is preventing your vehicle from starting.

    Turn the steering wheel to one side. One of the features of the 1997 Nissan is the wheel lock system. This prevents the vehicle from starting if the wheels are turned too far to one side or if the tire movement is obstructed by a curb. If none of the other solutions have worked, try putting the vehicle in neutral and moving the car, where you can do so safely, from obstructions to the tires and turning the steering wheel.

Infiniti G35 Transmission Problems

Infiniti G35 Transmission Problems

The Infiniti G35 was introduced in 2003; it was a mid-size luxury car available in coupe and sedan models. Edmunds.com reports that the G35 helped Infiniti regain a share of the luxury-market through its unique styling, interior room and sporty performance.

TCM

    Infiniti technical service bulletins report that one issue with the G35's transmission is its transmission control module. The TCM -- along with the powertrain control module -- controls the transmission through the use of computer sensors. An illuminated, check-engine light may indicate a failing TCM.

Harsh Shifts

    Technical service bulletins indicate that an issue with the G35 automatic transmission is harsh shifting; this is indicated by diagnostic trouble codes "P1710" and "P1716." The most common cause of harsh shifting is low transmission fluid. If replenishing the transmission fluid does not help, a transmission leak might be the culprit.

Transmission Range Switch

    Technical service bulletins report that a common, manual-transmission diagnostic code with the G35 is "P1702." This represents the transmission-range circuit. The transmission-range switch tells the TCM which gear the driver selects. If gear selections are not corresponding with the transmission's actions, the fault is likely with a transmission-range switch.

DIY Timing a 13B

The 13B motor in the Mazda RX7 is designed to be easy to time. If you notice a rough idling sound, or the motor shakes, start by setting the timing yourself to see if you can solve the problem without having to pay a mechanic. The timing will smooth out and prevent stressing engine mounts or exhausting excess fuel. Do the procedure in order, and you will straighten out the timing in a few minutes.

Instructions

    1

    Locate the leading and trailing marks on the main pulley. Stand on the driver's side to do this. The pulley is marked at the factory with the terms "Leading" and "Trailing." If your motor is old, these labels may have worn off, but you can still identify the marks by looking from the driver's side and seeing how they are grouped. The leading mark will precede the trailing mark by a few inches.

    2

    Identify the pin on the front cover. It is on the driver's side. You will need to use this pin to set the timing, so be sure you see it clearly. It is in line with the crank angle sensor, which looks like a distributor cap.

    3

    Connect your timing light to the leading coil pack. It is by the battery. You will find two wires. Either wire will work to connect the timing light. Place the timing light on one of the wires so that it will fire.

    4

    Shine the timing on the pulley. Check to see if the leading mark is lined up with the pin on the front cover. If it is not, use your hand to turn the crank angle sensor until you see the leading mark line up with the pin on the front cover. It will look like it is slightly off center once you have it adjusted correctly.

    5

    Locate the trailing coil pack by the brake master. Place your timing light on the front wire of this coil. You should see this wire fire on as the "trailing" mark passes. You cannot adjust the trailing mark timing. This is simply a double-check to see if your motor is working right. If the trailing mark is visible in your timing light during this check, your timing is correct.

How to Perform a Combustion Test

How to Perform a Combustion Test

A blown head gasket, warped head, cracked block or cylinder head can contaminate the coolant with combustion gases in your vehicle. These gases can turn your coolant into a very corrosive acid and seriously damage passages inside the radiator and many other components with which it may come in contact. If you suspect your coolant has become contaminated with combustion gases, examine the system with a block tester, a device similar to a turkey baster used to detect the presence of corrosive gases. It will save you in diagnostic expenses and from expensive repairs down the road.

Instructions

    1

    Prepare the block tester tool according to the manufacturer's instructions.

    2

    Install the block tester on the radiator filler neck or the coolant reservoir, depending on your particular model.

    3

    Start the engine and squeeze the bulb on the block tester one or more times, as directed by the tool manufacturer, to draw air from the cooling system through the liquid inside the block tester tube.

    4

    Watch the liquid in the block tester tube. If the liquid turns yellow, it is an indication of a compression leak.

    5

    Turn off the engine and remove the block tester from the radiator or coolant reservoir. Replace the liquid in the tester tube with new liquid and reinstall the tool on the radiator or coolant reservoir.

    6

    Remove one of the spark plug wires to short out that combustion chamber and repeat the test following steps 3 to 5. This will help you locate the combustion chamber with the leak.

    7

    Replace the spark plug wire and repeat steps 5 through 6 for each spark plug wire in your vehicle. When the liquid in the block tester remains blue, you have found the combustion chamber with the leak.

    8

    Turn off the engine and remove the block tester.

Minggu, 19 April 2009

The Symptoms of a Bad Transmission Solenoid

The Symptoms of a Bad Transmission Solenoid

Some vehicle problems can be difficult to diagnose. The transmission solenoid is a lever that keeps your car or truck in the correct gear and prevents the transmission from switching to drive, reverse or another gear. Without knowing the symptoms of a bad transmission solenoid, it can be hard to tell if the problem is with the solenoid or transmission itself.

Shifting Into Drive or Reverse

    One possible sign of a bad transmission solenoid is when your vehicle has trouble shifting into drive or reverse. Normally, when you start your car or truck, you're able to shift into drive or reverse right away. With a bad transmission solenoid, the vehicle could have a delay of a few seconds, or even take several minutes to warm up and operate properly. During this delay, the vehicle will act similar to how it behaves in neutral. It won't stay in park, and when you press the gas pedal, the vehicle will make an engine revving noise but not move.

Vehicle Does Not Downshift

    Sometimes, after the transmission solenoid goes bad, the vehicle does not downshift when you slow down. Even if you come to a complete stop, the transmission may not shift down. While still in a higher gear, your vehicle will have a harder time accelerating from the stop.

Vehicle Does Not Shift Into the Right Gear

    When the vehicle is accelerating, a bad transmission solenoid may not shift up into the proper gear. You can notice this because the car will have a rough ride and not accelerate as quickly as it normally would. Another similar symptom is that the car or truck will shift back and forth between gears while you are not changing speed. Generally you can feel a slight jerk as the vehicle shifts gears.

Over-Shifting

    The easiest symptom to notice is over-shifting. This happens when the solenoid allows the transmission to move more than one gear up or down. Over-shifting often happens when you stop pressing down on the gas pedal. The vehicle will experience a strong jolt as it jerks forward.

Diagnosing the Problem

    These symptoms are not the only way to diagnose a bad transmission solenoid. Many times, when you have transmission solenoid problems, your vehicle's "Check Engine" light will turn on. According to Engine-Light-Help.com, many of the codes given by your vehicle's computer will tell specifically what is wrong with your car or truck. Your mechanic or dealer can hook a scanner to your vehicle's computer to retrieve the "Check Engine" light codes.

How to Jump the ECM for Trouble Codes on a 1991 Chevy

How to Jump the ECM for Trouble Codes on a 1991 Chevy

Chevy vehicles manufactured before 1997 had a diagnostic system called On Board Diagnostics I. This is a diagnostic system monitors all sensors in the vehicle's electrical system and produces codes that help automotive technicians determine where to start when diagnosing problems.

Instructions

    1

    Unfold a paper clip until it is straight then fold it in half.

    2

    Remove the driver side kick panel with a screw driver set. There should only be two or three Phillips-head screws.

    3

    Locate the ALDL connector. This is a black rectangular 12-prong female connector located close to the center of the dashboard.

    4

    Turn off all electrical systems in the vehicle. This includes the heater controls and radio.

    5

    Insert the two ends of the paper clip into the A and B terminals of the ALDL connector. These terminals may or may not be labeled, but they will always be on the top right corner of the connector.

    6

    Turn the ignition key to the on position without starting the car.

    7

    Watch the service engine light. It will initially flash code 12. That means the system is in diagnostic mode. Every code the computer has stored will flash three times, each in sequential order.

Sabtu, 18 April 2009

What Causes Vibration in My Cold Truck Engine?

What Causes Vibration in My Cold Truck Engine?

Engine vibration can be a mystifying problem to solve even for the seasoned auto repair mechanic. Engine vibration can be associated with component failures that relate to engine performance while idling cold, or the cause can remain elusive until the suspect part responsible for the problem can be located and repaired. Narrowing down the problem with logical steps can be the only way to pinpoint malfunctioning parts, including systems that show signs of beginning failure.

Determining Engine or Chassis Vibration

    Start your engine and let it idle normally. After the first few minutes of start-up, listen and feel for any vibration in the vehicle. A sound like a buzz or rattling during cold running will most likely be engine-related. Any vibration felt in the steering wheel or on the clutch pedal, brake pedal or floorboard will also point to an engine component failure or out-of-balance engine part. If the noise decreases during driving, you can conclude that the problem cannot be related to the drive train, suspension or wheels.

Motor Mounts

    Check the condition of the motor mounts. Most vehicles have two front engine motor mounts, with an additional mount that supports the weight of the transmission. Motor and transmission mounts consist of thick pads or rubber shock absorbers designed to cushion the weight of the engine between the vehicle chassis. Any rubber or pad that has worn away will cause metal to metal contact between the engine and frame, causing a serious vibration. Bad motor mounts can often be detected during sudden acceleration, at which time the engine will lift up suddenly and drop, causing a very heavy clunking sound

Electrical Engine Misfire

    Any electrical engine misfire will be most prominent during cold start-up and idle. Check the distributor points in vehicles that have breaker point ignition. Burnt or improperly gapped ignition points will cause a constant engine miss that can be felt through the chassis. A burnt rotor or distributor cap, bad plug wire or defective spark plug can set up a vibration, since the misfire will unbalance the power stroke of the engine.

    For HEI (high-energy ignition) plug wires, rotor, cap and spark plugs should also be checked for proper firing, as well as the air gap setting in the distributor.

Fuel Misfire

    Make sure the choke setting has the proper adjustment for vehicles equipped with carburetors. A choke that does not close for cold-start conditions will not allow enough extra fuel into the intake manifold for combustion. A choke mechanism that does not disengage properly (open) will flood the engine and cause a noticeable stumble. The stumble will cause a cold-running vibration.

    For fuel-injected vehicles, the injectors must be checked for proper firing. Any injector that has shorted out will not fire and will cause a stumbling vibration. Fuel-injectors line should be cleaned, as well as the injector heads. Determine if the fuel pump regulator or fuel pump delivers enough fuel (pressure in pounds per square inch) to the intake manifold by using a fuel pump pressure gauge.

Fan Blades

    Cooling-fan blades can wobble on worn-out hubs or fan clutches, causing a very noticeable vibration. Any cooling-fan blades that have chips or are missing or broken should be replaced.

Pulleys and Balancer

    Check the harmonic balancer for any perceptible wobble or noise. The harmonic balancer has been designed to rotate at a specific engine frequency, providing the crankshaft with a smooth, even rotation.

    The crankshaft pulley at the front of the engine, sometimes called a dampener, can come loose from its key-way shaft and wobble. A misaligned crankshaft pulley can cause a very heavy vibration during cold running and disappear with higher engine rpm.

Clutch, Pressure Plate and Flywheel

    If your vehicle has a standard manual transmission, the clutch, pressure plate, throwout bearing and flywheel should be inspected. These heavy transmission parts can be bent, be loose from their mounts, or be broken and out-of balance. Cracked flywheels can rattle, causing chassis vibrations. Bad flywheels can sometimes be detected when the starter makes a loud noise upon engaging. Clutch, throwout-bearing and pressure-plate problems can be felt through the clutch pedal and cause the entire chassis to vibrate during idle in neutral, but disappear when the clutch becomes engaged or the vehicle moves.

Jumat, 17 April 2009

Problems Turning a Key in the Ignition

It can be a frustrating experience when you need to be somewhere, and the key won't turn in your car's ignition. The first thing to do is not to panic. In most cases a stuck ignition can be easily repaired within a few minutes. Relax for a minute and then follow a simple procedure to figure out what the problem is. Hopefully, it will only take a few minutes, and you will be on the road in no time.

Instructions

    1

    Examine the key to ensure that it is the right one. This may seem obvious, but in many cases, because of carelessness, forgetfulness or a simple mistake, you may be using the wrong key.

    2

    Inspect the key for signs of damage. Lay the key on a flat surface and look for dents, bent areas and broken teeth. Insert a spare key into the ignition and see if this corrects the problem.

    3

    Move the steering wheel back and forth while turning the key. Newer cars use a steering wheel locking mechanism as an anti-theft device. This makes it impossible to hot-wire the car and drive it away because the key has to be in the ignition to unlock the steering wheel.

    4

    Read the owner's manual for your vehicle. Some newer cars have safety features that prevent the key from turning in the ignition. Some vehicles won't start if a brake light is out. Others require the seat belts to be engaged before the vehicle can be started.

    5

    Check to see if the vehicle is in park if you are driving an automatic transmission. If the vehicle is a manual transmission, the brake pedal must be fully depressed with the car in first gear or reverse before the engine can be started.

    6

    Clean and lubricate the lock cylinder. Spray contact cleaner into the lock cylinder to remove any dirt and debris. Spray the lock cylinder with silicone to lubricate it.

What is the Cause of CV Axle Vibration

The constant velocity joints used on the inner and outer ends of a car's axle shafts are both complex in execution and oddly simple in principle. Normally, the CV joint's components mesh and roll together very smoothly, with almost no clearance between parts and nothing to throw the assembly out of balance. But any kind of damage can throw off the CV's careful balance, resulting in vibration at speed and under load.

CV Joint Construction

    There are two basic types of CV joints in use on the average car today: the "tripod" joint and the "Rzeppa" joint. On one side of a tripod joint are three small shafts sticking out of the end of the axle-shaft; encircling those posts are 10 to 20 or so tiny needle bearings, and around those are a metal "donut." These donuts fit into three large grooves in the "cup," which is on the wheel-side of the joint. A Rzeppa joint is similar in principle, but uses four to eight hemispherical balls on the shaft side with matching grooves on the cup side.

Excess Clearance

    Over time, the needle bearings in the CV joint will wear down and increase the clearance between the CV joint's internal components. When clearances increase, the components will hammer together under load, creating that tell-tale CV joint click under acceleration, deceleration and turning. This hammering drastically accelerates bearing wear, and will eventually start breaking parts. Once clearances get large enough, the CV mechanism will bounce back and forth inside the cup, causing shudder and vibration even under cruise conditions.

Broken Parts

    The bearings, bearing retainers and the cups will often break when the hammering action in the CV joint gets bad enough. Sooner or later, the whole assembly will just shatter like glass, leaving you with no mechanical connection between the transmission and the wheels. Actually, many cars will retain some connection; the rubber dust boot that connects the axle shaft to the other end of the CV. But, while the boot might keep the whole shaft from dropping onto the road, it will wrap up and snap back under load just like you'd expect rubber to. This constant wrap-unwrap cycle is one major cause for vibration with a broken CV joint.

Imbalances

    Your wheels use small weights to offset tiny imperfections in the tire and wheels, because any imbalance in the assembly will cause the wheel to bounce and vibrate. CV joints and axle shafts typically aren't as sensitive to minor imbalances because they're so small in diameter; it takes a pretty serious imbalance to get a CV joint vibrating linearly with speed the way a wheel will. But broken internal components slung outward to the inside of the dust boot by centripetal force, as well as bent axle shafts and axle shafts that flop around within the dust boot (as a result of broken internal components) can all cause an imbalance-type vibration that increases with speed irrespective to load or steering angle.

Kamis, 16 April 2009

What Causes Error Code 304 on a PT Cruiser?

What Causes Error Code 304 on a PT Cruiser?

Many engine and other various car troubles are diagnosed with error codes. These error codes on the PT Cruiser are visible on the dashboard in the odometer reading when the key is turned on, off, on, off, and then on again. "On" is the position just before "Start." When this is done properly, the error code will display where the odometer reading usually is. Sometimes, the combination has to be performed more than once for it to work. If there are no codes to list, the reading will say "Done."

Error Code 304

    The engine of the PT Cruiser is a highly computerized machine with hundreds of error codes specific to its different areas. The error codes tell the mechanic exactly what the problem is and where it is located. Error code 304 indicates that a misfire has been detected in cylinder number 4.

Causes of Misfire

    Engine misfire is caused by one of three things: loss of spark, unbalanced air to fuel mixture, or loss of compression. A mechanic will be able to tell which is the cause and repair it.

Reset Error Codes

    Resetting the error code and getting rid of the "Service Engine Soon" light on the dashboard can only be done once the problem is fixed. Once fixed, the error codes need to be reset using an error code scanner.

S-10 Troubleshooting

S-10 Troubleshooting

Drivers who want to troubleshoot their S-10 vehicles do not have a hard task. The S-10 remains very close to the way it was when it first came on the scene in 1982. Available options include engines of the V-6 or four-cylinder variety, as well as two- or four-wheel drives. If you know what to look for, you can troubleshoot S-10s with little effort.

Instructions

    1

    Verify that your vehicle contains all of the fluids it needs, such as radiator liquid, oil and transmission fluid. If fluid levels are low, you may notice that your engine makes abnormal noises or loses its ability to accelerate. Note that you should replace your fluids on a bi-annual basis.

    2

    Ensure that no leaks exist. For instance, if you have a leaky transmission, look for a liquid that appears red and gives off a sweet scent. If your engine contains a leak, look out for a liquid that contains a black or dark brown tone. Finally, gas itself has an easily recognizable fuel smell. Note that you may need to utilize your flashlight and look deep into the dark areas of your engine to find the location of a possible leak.

    3

    Check if the spark plugs, tubes and wires that lie under your hood connect in the proper manner. If you find a wire or part that appears not to connect properly, you can put it back in on your own or simply bring it to a mechanic and describe what should be reattached.

    4

    Charge your vehicle's battery, then try to crank it. This enables your starter to turn over the engine until your battery no longer has any more power.

    5

    Write down the error that you see. For instance, if you notice that your vehicle states the words "Check Engine Soon," this means that you have an issue with your engine. When you bring your car to a dealership in your area, the technicians have the ability to search for specific codes unique to your S-10 vehicle in their system to let them know exactly where the problem lies.

1990 Honda Civic Troubleshooting

The 1990 Honda Civic sedan featured a 4-cylinder engine and manual transmission. The car also featured a number of safety features including side airbags. The 1990 Honda Civic was also available as a hatchback with some of the same features. As a Honda Civic owner, you may experience an occasional problem with your car. Some issues may be resolved without the need to call your mechanic. Basic troubleshooting can help you save the expense of a diagnostic or simple repair.

Instructions

    1

    Check the oil levels in your 1990 Honda Civic if the oil pressure warning light is lit on the dashboard. The light is an indication that your car is either low on oil or the light has failed. Let your car rest for a moment and raise the hood. Remove the oil dipstick located near the engine. In the Honda Civic, the dipstick will be labeled "Oil." Wipe the dipstick clean with a paper towel and replace it in the hole. Remove the dipstick again and make note of where the oil level is. If it is low according to the lines on the stick, add more oil to your car. Check the oil level again and start your car. If the light stays on, the warning light may be the problem.

    2

    Check your coolant levels if your Honda Civic overheats while driving. Pull your car over and allow it to cool off. Raise the hood of the car and remove the radiator cap. If steam starts to come out when trying to remove the cap, do not continue. Allow the car to cool further. If the coolant level appears to be lower than the line marked on the side of the coolant reservoir, add more coolant. Replace the cap and lower your hood.

    3

    Check the amount of brake fluid in your Honda Civic if the brake warning light is active on your dashboard. You should also check the levels if the brake goes all the way to the floor when the brake is depressed. Raise the hood of the Honda Civic and locate the reservoir for the brake fluid. The reservoir is located near the engine of the car and is labeled "Brake." If the amount of brake fluid is not to the level indicated on the reservoir, add more brake fluid. Replace the reservoir cap and close the Honda Civic's hood. Start your car and check for the brake warning light.