I figured i would search for problems tonight with other people's b6s' and see if they had similar issues i had w/ mine. And i found out i had a good amount of these problems so far from auditech79's posts... so here goes... any useful help/comments/flames/questions is appreciated. Bought my 3.0liter a4 regular package like 1.5 years ago at crappy san rafael dealership and it's been trouble ever since (although it drives real nice when it's working). Bought it with 69k miles on it, and now i've accumulated up to 82k+ miles. Don't kno much about cars.

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1. Overheating, when your gauge is telling you that the engine is overheating, your very first step is to verify that it is indeed overheating. Open the hood and check the coolant lines with your hand, look at the coolant resivior, overheating causes the coolant tank to boil over and lose coolant. Feel the radiator, if it feels cold the thermostat is stuck closed and needs to be replaced. If the radiator is warm (but not hot) but the hoses feel hot as hell going into the radiator you probably have a bad water pump. These both happen around the 60-80k mark. Replace the timing belt, water pump, thermostat etc. and you won't have any more problems.

i paid like 3 grand to fix this problem at some mechanic that my relatives recommended, i forgot exactly what he did, can't find my receipt. Car temp gauge showed above mid point about a week of owning my car... got scared, tried to drive it to the mechanic and then the temperature warning light came on because the car got too hot (needle was pointing between midpoint and Hot on the gauge) so i had to have it towed to the mechanic. Mechanic said some sensors were old and the engine block or some part needed to be polished/grinded to smooth it out again... all in all, i got it back like 2 weeks later and it ran fine... at least it seemed...

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2. CTS sensors, the black sensors are faulty, and will cause gauge malfunctions, increased fuel consumption, rich fault codes, excessive cranking times when the engine is warm, and even random misfire faults. Replace with a green top sensor to cure these issues.

i'm not sure if this problem falls under this category but here goes... 2 months ago i think my engine had sounds that were subtle but noticeable that the engine sounds weren't as smooth as before, and my driver seat sort of vibrates on my left thigh when i turn on the cold car early in the morning. No warning lights, so i ignored it. Then one day the engine light turned on, and when it was left on park, the idle would be unsteady, rpm needle would swing back and forth below and above 1. I drove that **** like that to the mechanic, on the way there on the freeway, i could sense that the power in the car had dropped, not very responsive to the gas peddle. I finally reached the mechanic, he stuck the computer diagnostic reader thing under the steering wheel and it showed that the "camshaft" sensors were malfunctioning.

Then he said my valves are probably bent cause he checked with some air utensil, and he had to change my coils too i think, and replace engine head, spark plugs, changed my valves, changed my sensors and maybe spark plugs, and i ended up paying another 2800 bucks. After a week i got it back, it leaked engine oil and he said the part he used for my engine is faulty, he will fix that for free.

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5. Humming noise upon start up. If you hear a humming noise upon start up that lasts for about 5-8 seconds, replace the fuel pump filter.

10. Auxillary fan stays on after the key is shut off. This is generally caused by a faulty fan control module and it requires some major wiring work, if you are not mechanically inclined or know how to cutt and splice wires take the car to the dealer.

11. Auxillary fan comes on all the time the engine is on. There is a lot of things that the fan gets input from, the common problems are the two CTS sensors. Replace BOTH of them and double check concern. If this doesn't fix it, you cannot go any further and it has to be diagnosed at the dealer using a pin out box. A pin out box basically plugs into the ECM harness so the tech can trace power/resistance to each of the 300+ wires in the engine harness.

I hear humming noise when i turn on the car in the morning, i think it's from the radiator fan... and my mechanic (same one) says it's because the fan is on and is warming up itself in the morning, the fan will quiet down in a minute or so and that it's normal... (is he making sense?) and does this problem if even considered a problem fall under problems #5,10, or 11?

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13. Vibration issues. I'll make this very clear, vibrations can only be cause by a rotating componet. Example: Wheels, tires, brake rotors, or drive shafts. Replacing control arms for this is like pissing in the wind, you're not gonna get the result you want..
Your first step in diagnosing a vibration is to have the wheels spun on a balancer, if no problems can be found with the wheels, have the rotors measured for out of rounds. If either of these methods do not work put the car in the air, disable the ESP, and drive the vehicle up to about 60mph while someone else looks at all four wheels. If you see a specific wheel that is shaking more than normal, take that wheel off and install the spare tire and have the affected wheel replaced and or new tire. If two wheels are flopping out of control then you may have a propshaft problem (NOT LIKELY) Now if all FOUR wheels are wobbling and these are after market wheels, order hubcentric centering rings for all four wheels. Aftermarket wheels are drilled with a larger hub than stock audi wheels and need a spacer to fill in the gap to keep the wheel from wobbling.

My car vibrates, i can feel it on the driver seat, steering wheel and shift **** when i cruise between 75-80+ mph, I don't kno if my car has had this problem before or after i bought it. I tried to get a wheel alignment done one day since it slightly drifts to the right and my mechanic says it's the control arm bushings, and i should replace the front ones to fix the problem. So what do you guys think will fix the problem?

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17. 3.0L coolant leak. If you find that you are losing coolant but aren't overheating check behind the motor. If you see crusted dried up coolant, you are most likely leaking from a little nipple on the coolant cross over pipe. You will see a little 1/4 hose going straight into the pipe, the little nipple is what the hose connects to, replace the nipple and crush washer. Another cause could be the cross over pipe itself, which is a PITA to replace.

I had this problem when i first bought the car, the dealership charged me $100 to replace it, even though the car came with a crack at the bottom of the coolant reservoir which i saw dried pink coolant on with dried droplet shaped coolant on the outside of it and drips on some of the plastic wire protection covers.

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19. Power steering whine. If you hear whining from the power steering pump check the fluid. VW/Audi power steering fluid is a mineral based fluid that will evaporate over time. It has to be topped off every 15k, so keep some in stock in your garage. After adding fluid you have to aerate the fluid. To do this, leave the cap off the P.S. resivior, and turn the wheel lock to lock until the sound goes away.

I'm not sure if this falls under this category but when i turn my steering wheel all the way to the left or right, the car makes a pretty well defined sound of screeching/squeeking/whistling sound. Not sure if fixing the control arm bushings willl fix this problem... What do you guys think?

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21. Sunroof acting possessed. If you notice that your sunroof is acting like its being controlled by the devil, then chances are the switch (potentiometer) is dirty or faulty. What you should do first is take out the switch (above your head) and clean the contacts with some electrical contact cleaner, then give it a try. If it doesn't work the way it should just replace the switch, its not a very expensive part.

My sunroof is acting possessed but i noticed when i open the sunroof cover, the cover itself does not slide all the way back, just half way, so that the most i can pull back reveals only half of the sunroof, obviously i knew then it was broken, because even when it closes all the way, i can see that the sunroof cover is not completely on the rail, one side is slightly but visible off the sliding rail, and i'm guessing thats y it gets stuck when i pull it back, and when i use the switch to open the sunroof completley i can tell the gears are struggling and if i just use the switch just to raise the sunroof all the way, sometimes it would close on its own. Im guessing the broken sunroof cover being off its rail has something to do with it. I have no solution on how to fix this other than to pay the mechanic to remove the roof to check... What do you guys think?

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P.S. Sorry if this body of text depresses any of you.