Help needed with 2.7T misfire problem - PO300
After 35k miles (total of 79k on the car) I am having my first real problem with my 2004 Allroad that I cannot seem to easily solve.
I have been having a heck of a time with this issue. My car started acting up last Friday on the drive home. By that, I mean you could feel sudden misfires and lack of power. Feathering the gas pedal was the only way to got it home.
1) Pulled all spark plugs - all were beige and clean. Changed plugs while in there and also added some drygas to the tank just in case water got in there.
2) I pulled codes - got 306 initially. Swapped cyl 6 Coil with another cylinder, cleared codes. Test drive was 5 minutes and the problem started to "feel" worse. I rescanned the car and now found codes 300, 301, 303, 304, 305 and 306 - all but one were misfiring.
3) Getting worried, I removed the timing belt cover. I could not see any visible signs of trouble. The belt appeared to be fine.
4) I changed the Fuel filter. When the nut was cracked loose, serious pressure forced some fuel out. Not a valid pressure test but a good indicator. No improvement on next startup.
5) I pulled one plug from each bank and ran a cranking compression test. Both sides still have 120PSI.
6) I unplugged the cam timing sensor on the Driver side. No change in behavior other than the expected code of 020.
So, I think I have ruled out injectors, coil packs, fuel filter and plugs for sure. Things now may get expensive.
One more thing. The car idles badly now too. The engine shakes visibly in the engine compartment. Again, all the plugs where clean after limping home and before changing them anyway. This same problem occurs when the car is cold or warmed up so guessing it is not an EGT sender or O2 since both take time to heat up.
I tried calling Audi of Nashua to see if a tech would be willing to spend just a few minutes with me. I was almost floored when I was told that the techs were busy trying to make a living and that they do not like to give advice for free. After that, the service rep said he'd see if he could talk to someone for me. They have not called me back and now I would not take my car to them ever again.
The day the problem started was also one of the hottest days of the year out here - not sure if this could be a clue or if it could have contributed so sensor failure.
Any thought or ideas would be much appreciated!