Question about 2004 Audi A4

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2004 Audi A4 misfire

Engine keeps throwing misfire codes and have replaced 3 of 4 coil packs as they burn out. When check engine light comes on, have scanned with VAGCOM to find one cylinder at a time missing due to coil packs and replaced said coil packs. Today, #3 misfire code has appeared, swapped with #4 coil and misfire code went to #4 cylinder. Bad coil. pretty straight forward but WHY does it keep happening? Have also read on some VW/Audi boards that certain models need genuine VW/Audi coil packs (updated circutry or something?) or vacuum leaks or MAF sensor can trigger misfire codes. There is only one original coil pack left but it seems to be holding up.

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  • Aaron Perry May 11, 2010

    What data codes were you getting?



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It is always a good idea to stay with o.e.m parts and yes there is updated parts in the newer coils. and yes the M.A.F will also cause misfire faults but will not make check engine light flash or make car shake and shudder. also check you wire harness going to your coils make sure your ground wires are not cracked. That could be the main culprate. good luck hope this helps

Posted on Sep 03, 2009

  • bs77bird Sep 03, 2009

    if you have vagcom go into engine electronics check measure value block 32 that will tell you your m.a.f idle and cruise air mixtures. they should be very close. also if either are over 25% your maf is toast. look at the breather and vacuum hoses under your intake manifold. good luck hope this helps



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