Eduardo Valdivia

I started having problems with my 2007 Q7 4.2 L late last year, when I floored the pedal and nothing, only high RPM reading but no monster acceleration like I was used to. The check engine light is turned on. When running in the city at normal speeds, all seems normal and the car runs fine. It is only when you force it at high speed or when going uphill that it stalls and you get no acceleration.

So far I have done the following and I still have the same issue at high RPM:

- Changed all spark plugs
- Changed all ignition coils
- Changed all O2 sensors
- Changed the 2 high pressure fuel pumps with sensors
- Checked for vacuum leaks and nothing appears

I am still getting the following error codes:

- PO304, cylinder 4 misfire
- PO302, cylinder 2 misfire
- PO303, cylinder 3 misfire

Can anyone please give me any clues on what to try next?? My bigger problem is that I am at a town in Bolivia South America, with no Audi support whatsoever, so I have to rely on parts brought from the US.

Thank you very much!!!

Peter1802

Chachboi

With the engine running, take a big long screwdriver and set it on the top of the rear timing cover and put your ear on the back of the handle, listen for any kind of rattling or tapping. If there is it is most likely a timing component (i.e. Cam adjuster or chain guide). If it sounds nice and smooth then remove and check your camshaft adjuster solenoids for any metal mesh stuck inside the ports. if both check out good try swapping the three bad coils with 3 good ones, clear codes, and run it to see if they change location.