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Tuesday, January 30, 2007

VW P3801

VolksWagon Check Engine Light Code "19537 4C51 P3081 Engine temperature too low" That DTC is indicative of a missing thermostat, a stuck open thermostat, or a cooling system with 100% antifreeze. It is NOT associated with a defective ECT G62. When the coolant temperature is too low, that does not necessarily mean a sensor failure. Sounds like the sensor is telling you the truth. Watch the temperature on the scan tool as the engine warms up. Look for things that keep it from warming up. Things like radiator fans on all the time, straight anti-freeze, stuck open thermostat and so on. That is what it means. It means a system problem, not necessarily a component failure. More....

Sunday, January 28, 2007

Brake Pad Break In Procedure

BRAKE PAD BEDDING IN PROCEDURE To ensure maximum performance and customer satisfaction, new brake pads must be bedded in upon installation. Correct bedding guarantees that new brake pads and new rotors work flawlessly together. In order to function optimally, organic brake pads must develop friction coal on its surface. This friction coal develops at a temperature of approximately 280°C (537°F). It is very important that this temperature is reached continuously and slowly. This gradual process generates temperatures that not only penetrate the surface of the brake discs and pads, but also distribute evenly through the whole disc and pad material. This is essential when using new brake discs, since the disc often shows signs of stress (due to the casting process and fast cooling) in the materials. A steady and careful warming and cooling process guarantees a good release of both materials. The bedding in/break in procedure should be done as follows: Drive at approx. 35 mph (60 kmh) for about 500 yards (solid front discs) to 800 yards (vented front discs) while slightly dragging the brakes (i.e. light brake pedal pressure). This process allows the brake temperature to slowly and evenly build up to 300°C (572°F). Now, if possible, drive about 2200 yards maintaining the same speed without braking. This will allow the pads and discs to cool down evenly. After this cool-down, perform a normal brake application from 35 mph to 0. No panic stops! Now, the friction surface has evenly developed friction coal, the pads have bonded with the disc surface, and tensions in the disc materials will have disappeared. Only trained master mechanics should perform this procedure before delivering the vehicle to its owner. Do not expect your customer to properly finish your brake job! This bedding process is only suitable for the front axle - not the rear. This is due to the brake force distribution of front and rear axles. In order to reach 300°C (527°F) on the rear pads you would have to drive several miles with dragging brakes. However, in that time the front brakes will be glowing red, overheating and thus destroying the front brakes. Final note – don’t forget to clean hubs and check the wheel bearings. Also, the brake fluid should be replaced at least every 2 years.

Wednesday, January 24, 2007

Bleeding Brake Systems

NON-ABS SYSTEMS When any part of the hydraulic system has been disconnected for repair or replacement, air may get into the lines and cause spongy pedal action (because air can be compressed and brake fluid cannot). To correct this condition, it is necessary to bleed the hydraulic system after it has been properly connected to be sure that all air is expelled from the brake cylinders and lines. When bleeding the brake system, bleed one brake cylinder at a time, beginning at the cylinder with the longest hydraulic line (farthest from the master cylinder) first. Keep the master cylinder reservoir filled with brake fluid during bleeding operation. Never use brake fluid that has been drained from the hydraulic system, no matter how clean it is. It will be necessary to centralize the pressure differential valve after a brake system failure has been corrected and the hydraulic system has been bled. The primary and secondary hydraulic brake systems are individual systems and are bled separately. During the entire bleeding operation, do not allow the reservoir to run dry. Keep the master cylinder reservoirs filled with brake fluid. Wheel Cylinders and Calipers Fig. 1: To bleed the front brakes, place one end of a clear hose on the bleeder screw and the other in a clear container of brake fluid Clean all dirt from around the master cylinder fill cap, remove the cap and fill the master cylinder with brake fluid until the level is within 1⁄4 in. (6mm) of the top of the edge of the reservoir. Clean off the bleeder screws at the wheel cylinders and calipers. Attach the length of rubber hose over the nozzle of the bleeder screw at the wheel to be done first. Place the other end of the hose in a glass jar, submerged in brake fluid. Open the bleed screw valve 1⁄2 – 3⁄4 turn. Have an assistant slowly depress the brake pedal. Close the bleeder screw valve and tell your assistant to allow the brake pedal to return slowly. Continue this pumping action to force any air out of the system. When bubbles cease to appear at the end of the bleeder hose, close the bleed valve and remove the hose. Check the master cylinder fluid level and add fluid accordingly. Do this after bleeding each wheel. Repeat the bleeding operation at the remaining 3 wheels, ending with the one closest to the master cylinder. Fill the master cylinder reservoir. Place the clear plastic hose over the wheel cylinder bleeder screw and the other in the clear container of brake fluid when bleeding the rear brakes Master Cylinder Fill the master cylinder reservoirs. Place absorbent rags under the fluid lines at the master cylinder. Have an assistant depress and hold the brake pedal. With the pedal held down, slowly crack open the hydraulic line fitting, allowing the air to escape. Close the fitting and have the pedal released. Repeat Steps 3 and 4 for each fitting until all the air is released.

Friday, January 12, 2007

Radial Tires, What does it mean ?

RADIAL The simple definition of a Radial type tire: The radial is a type of tire that is constructed with rubber coated, reinforcing steel cable belts that are assembled parallel and run from side to side, bead to bead at an angle of 90 degrees to the circumferential centerline of the tire. (As opposed to the 30 degree alternating application lengthwise as in bias ply tires). This makes the tire more flexible which reduces rolling resistance to improve fuel economy. Then numerous rubber coated steel belts are then constructed into the "crown" of the tire under the tread to form a strong stable two-stage unit. Performance and purpose of Radial tires Radial tires are the preferred tire of choice in most applications for several key reasons. The combination of steel stabilizing belts in the single-layer radial casing allows the tread and sidewall to act independently. The sidewall flexes more easily under the weight of the vehicle and its cargo, while the tank-track type tread provides even contact with the ground. Greater vertical deflection is achieved with radial tires. This is desirable because extreme flexing greatly increases resistance to punctures. To increase a radial tire's strength, larger diameter steel cables are used. Larger steel cables can help reduce punctures, tears and flats. Larger steel cables also help distribute heat, resulting in a cooler running tire and improving fuel economy. Unlike bias ply tires larger steel cables have little negative affect on performance. The parallel stabilizing steel belts of the radial minimize tread distortion. As the sidewalls flexes under load, the belts hold the tread firmly and evenly on the ground or object and thus minimizing tread scrub and greatly increasing tread life. When cornering the independent action of the tread and sidewalls keeps the tread flat on the road. This allows the tire to hold to its path. When offroad, the radial tire's stabilizing steel belt design aids in greater traction by holding the tread evenly over obstacles allowing the tread of the tire to have a better chance of finding traction.

Radial Tires, what does it mean ?

RADIAL The simple definition of a Radial type tire: The radial is a type of tire that is constructed with rubber coated, reinforcing steel cable belts that are assembled parallel and run from side to side, bead to bead at an angle of 90 degrees to the circumferential centerline of the tire. (As opposed to the 30 degree alternating application lengthwise as in bias ply tires). This makes the tire more flexible which reduces rolling resistance to improve fuel economy. Then numerous rubber coated steel belts are then constructed into the "crown" of the tire under the tread to form a strong stable two-stage unit. Performance and purpose of Radial tires Radial tires are the preferred tire of choice in most applications for several key reasons. The combination of steel stabilizing belts in the single-layer radial casing allows the tread and sidewall to act independently. The sidewall flexes more easily under the weight of the vehicle and its cargo, while the tank-track type tread provides even contact with the ground. Greater vertical deflection is achieved with radial tires. This is desirable because extreme flexing greatly increases resistance to punctures. To increase a radial tire's strength, larger diameter steel cables are used. Larger steel cables can help reduce punctures, tears and flats. Larger steel cables also help distribute heat, resulting in a cooler running tire and improving fuel economy. Unlike bias ply tires larger steel cables have little negative affect on performance. The parallel stabilizing steel belts of the radial minimize tread distortion. As the sidewalls flexes under load, the belts hold the tread firmly and evenly on the ground or object and thus minimizing tread scrub and greatly increasing tread life. When cornering the independent action of the tread and sidewalls keeps the tread flat on the road. This allows the tire to hold to its path. When offroad, the radial tire's stabilizing steel belt design aids in greater traction by holding the tread evenly over obstacles allowing the tread of the tire to have a better chance of finding traction.

Tuesday, January 09, 2007

No Start Condition

Now that we are getting into winter some of us find that are having trouble starting. An Engine needs four basic things to allow it to run. It requires Spark, Fuel, Compression and at the right Time. Older vehicles ( pre - 1986) had carburetors that would cause a vehicle to flood themselves in the winter. Now that technology has stepped into play there are mostly fuel injected vehicles on the road, give or take a few hybrids. The Majority of No starts are caused from battery failure . Even if the battery is heavily corroded or just a loose connection. The vehicles computer controls the fuel system and on the latest of vehicles controls the starter. Test your battery at every service. Keep your battery terminals clean. Make sure you have over a 1/4 tank of fuel all winter long.

Monday, January 01, 2007

Save Money with Maintenance

HAPPY NEW YEAR !!!!

Make it a new years resolution to keep up on your vehicle maintenance that will save you both time and money. Think of the down time when your sitting along side the road with a flat tire or stuck at the air port because your car won't start. I don't need to tell you how much calling the tow truck costs.

The best and most efficient method of knowing about your car and keeping track of it is through the owner's manual which provides complete information on how to go about it. You can inspect your car every time you enter it, or on a daily or weekly basis or at intervals specified in the manual.

Must do's : Change the engine oil every 3,000 miles. oh but the book says every 5,000.....ask your self this " how does a vehicle manufacturer make money??" By selling you a new car !!! They only need the vehicle to last as long as the warranty. You can have it last longer buy properly maintaining your vehicle and have less problems. Yes, there are vehicles on the road with over 500,000 miles on there engines!!!!!

Keep a close eye on your tires. Check the pressure at each oil change and look at the tread depth across the entire surface. Anything below 3/32" and you are looking for trouble .

Check your battery for corroded terminals and have it load tested at each oil change.

If you follow these basic maintenance tips you are looking to save time and money in this New Year and the next !!!!

Friday, December 22, 2006

CODE PO401 : Insufficient EGR Flow

The Exhaust Gas Re circulation (EGR) system is designed to reintroduce exhaust gas into the combustion chambers, thereby lowering combustion temperatures and reducing the formation of Oxides of Nitrogen (NOx). The amount of exhaust gas that is reintroduced into the combustion cycle is determined by several factors, such as: engine speed, engine vacuum, exhaust system back pressure, coolant temperature, throttle position. All EGR valves are vacuum operated. The EGR vacuum diagram for your particular vehicle is displayed on the Vehicle Emission Control Information (VECI) label. The EGR system is Differential Pressure Feedback EGR (DPFE) system, controlled by the Powertrain Control Module (PCM) and composed of the following components: DPFE sensor (also referred to as the back pressure transducer), EGR Vacuum Regulator (EVR) solenoid, EGR valve, and assorted hoses. The P0401 code means that OBD detected an insufficient amount of EGR. Symptoms There may be drive-ability issues such as pinging ( pre-ignition knock , similar to cheap gas) when the vehicles engine is under heavy load or the vehicle is climbing a steep grade. There may also be other symptoms. Causes A code P0401 most likely means one or more of the following has happened: The DPF (differential pressure) sensor is faulty and needs to be replaced There is a blockage in the EGR (most likely carbon buildup) The EGR valve is faulty The EGR valve may not be opening due to a lack of vacuum Possible Solutions In fixing this code, it is quite common for people to just replace the EGR valve only to have the OBD code return. The EGR valve is not always the cause. If you replace all 3 components the like is all but guaranteed to go away . Or you can test each component . Use a vacuum pump and pull the EGR valve open while monitoring engine RPM's. There should be a noticeable difference in RPM's with the EGR open Clean out the EGR valve to remove deposits Replace the DPF sensor Replace the EGR valve

Friday, December 15, 2006

Diagnosing Your Brakes

Brake problems vary greatly with the make and model of a car, the age of the car and other variables. If your car is experiencing brake problems, bring it to a mechanic. You may, however, be able to narrow down some of the possible problems yourself. Below are some general guidelines. Followed by some helpful troubleshooting hints.
  1. Step off the brakes, with the car's engine turned off. A soft or mushy brake pedal indicates that you may be low on brake fluid, or may need to bleed your brakes.
  2. If it is safe, drive the car at low speed, braking as needed. You may need new brake pads, or to clean the brakes, if they squeal.
  3. In a clear area, step sharply on the brake pedal. If the brakes do not stop the car effectively, several things may be wrong, including worn pads, contaminated brake fluid or contaminated brake pads.
  4. If the brakes pull the car to one side, you may need to adjust the brake's clearance, may have to replace the pads or rotors, or may have insufficient hydraulic pressure in one part of the brake system.
  5. Begin driving forward slowly. If the brakes bind or drag, it may be due to grease on the pads or scored rotors. Visit a mechanic if you do not know how to fix brakes. Describe the car's performance to the mechanic in as much detail as you can. Check brake fluid regularly. If you have determined that your brakes are bad, avoid driving the car until they are fixed. Computerized brakes, which are standard in many cars, need to be fixed by a mechanic.

Tuesday, December 12, 2006

MAINTENANCE

Benefits of Proper Maintenance The automobile is a truly amazing machine. It is expected to function under a wide range of weather conditions and other adverse conditions, yet it often is subjected to careless hard driving and indifferent maintenance. Recommended service intervals are often ignored by the same vehicle owners that wouldn't let a week go by without vacuuming all the rugs in the house. Today the automobile is an integral part of our life. We have come to rely on the proper functioning of the family vehicle and seldom, if ever, make a time allowance in case the vehicle should fail to start. We expect it to start and move every time, and fortunately, most of the time it does. However, the rare instance that it doesn't, causes the owner to forget the thousands of times it started without a problem. The irony is that, chances are, the vehicle failed to start because of neglect. A periodic maintenance program such as the one in this book can keep the vehicle owner more aware of the condition of his or her vehicle and will save money in three important areas-fuel economy, emissions and performance.