I have 03 A4..this morning this started:

when getting around full boost my car studders and the CEL starts blinking, when i let off the accel the CEL goes off.

almost at work this morning, the CEL goes on and stays on, i take it to autozone to get the CEL code, and it says misfire cylinder #3..

Now the CEL is off again untill i get to full boost and its back to blinking then off when i let off.

I checked the coil packs, ground wire, spark plugs but still..

I recently replaced the timing belt, WP, coil packs, spark plugs (NGK) all 2 months ago.

I checked for Vacuum leaks and didnt find anything.

My car is chipped, and I am no longer getting normal full boost which is usually 20psi, now im only getting around 10..maybe in LIMP mode?

any ideas on how else to diagnose the prob???

 

I was going to say coil packs but yours are pretty new. I had to go through 3 sets within like 2 months maybe its that again but i am not sure. The dealership did say they have been having a lot of problems with the coil packs lately

 

Coilpacks, im 99% sure )))))))))))))))))))))
doesnt matter if they are new or not...
i had 3 different types of coilpacks and each of them went bad on me at least once...
my last set was STi coilpacks, when 2 of them went bad, my car was still driving normal when NOT in boost, and was misifiring under heavy boost... which was the opposite when OEM coils went bad on me --- car was misifiring even at idle.
replace coil #3 and see if your problem is gone

 

Ok, so i swapped my 2month old #3 coil pack with an older one that was replaced and what do you know.. problem solved!

how the hell does a 2 month old coil pack go bad?

oh well.. relieved that it wasnt anything serious...


thanks for the help guys

 

Crappy manufacturer. Even if its 'OEM' its usually not the same manufacturer as when the car was new.

 

limp mode only exists in auto transmissions.... not your turbo system

 

Um no. There is an auto transmission limp mode and an engine limp mode. Put an MBC on a 1.8T and go over 15 psi, this will put the engine in a limp mode limiting the boost to less than 5 psi and pull the timing, plus it won't illuminate the gear selectors.