My car is a 05 Audi A4. I have taken it to the dealership 4 times now and all 4 times for the #3 cylinder misfire. I have changed all the coils twice, spark plugs once and cleaned the entire fuel system once.

The last time it was at the dealership. They reset the ECU for troubleshooting; which to me seemed weird. However, after resetting they could not get the problem to duplicate and that was 3 weeks ago. Which leads me to now, I could get them to reset again but I want the problem fixed.

Here is what I do know. The car is fine at idle. Drives fine all around town fine. However, above 60mph it hesitates and the CEL flashes till I slow down and maybe give it a little gas. Going up hills; forget about that it just stubles. If I stay in it the CEL will just stay on. Lately, I just let off. This was me trying to get home last night from out of town and was an hour out. I just took notes in hopes that someone could help me figure this out.

I know it is the misfire again because I have a generic OBDII scanner.

For all those that can assist, Thank you ahead of time
Carlos

 

2.0 or 3.2?

 

Sorry, it is the 2.0T, Quattro, tiptronic and all stock

 

hmm ive never heard of a problem like this but my initial thought was carbon buildup but the problem seems to specific to be that. It does sound like a fueling problem, maybe either the lpfp or the hpfp not keeping up under load. Have u tried going WOT (wide open throttle) at lower gears to see if the CEL comes on? If not try slamming on it in 1st or 2nd to see if it comes on under load.

Otherwise id look into changing the cam follower which is located right under the hpfp.

Also what kind of gas are u putting in it? should always be 91 or 93

 

I have put nothing below 91 in the car since I have owned it. I can't remember it I have tried to go WOT to see if it comes back under load. I will try and post the results.

I sure it will considering I do not know the grade of the hill here in town. It barely made it up the hill but was fine before that.

 

Went WOT in 1st, 2nd and 3rd on the way to work last night and nothing. Car ran like a champ. No hesitation, no misfire and no CEL.

 

Ok, what about when you drive it on hills now? Sounds electrical, but that's just me. So you say the problem goes away if the ECU is reset? If so, then something is probably up with the computer.