speedshifter

I've been struggling with a misfire issue issue for over a week on my 2004 Audi S4. I first got a P0306 and P0308 code. Cylinder 6 & 8 misfire on bank 2.

1) I first tried replacing the ignition coils. Still having the issue.
2) I put in fuel injection cleaner. Cylinder 6 cleared up but misfire continued on Cylinder 8
3) I have had the car compression tested and pressure was between 170-180 across all cylinders. 4) I replace all four fuel injectors on bank two. However the P0306 and P0308 came back.

I started to notice that I had issues trying to start the car a month ago. I would turn the key but the engine wouldn't turn over right away. Could a bad fuel pump relay or bad fuel pump cause this misfire. PLEASE HELP.

bearthebruce

Testing an Audi with a generic OBD-II scanner will give incomplete information. I'd be willing to bet you have many more fault codes than what the OBD-II scanner is reporting. The shot gun method of resolving these problems usually leads to the frustration you are experiencing.

I suggest you find someone near you who has a VCDS (VAG-COM) system and run full diagnostic scan of the car. Post the results here and I am sure members will be pleased to try to help.

To see more about Generic Scanners versus a factory level tool, see this article on the Ross-Tech web site: http://www.ross-tech.net/vag-com/adv...nerTechTip.pdf