Stumped on rough engine - not coils I think
#1
Stumped on rough engine - not coils I think
Hi all,
I'm a long time reader, first time poster. These forums have helped me so many times with my 2000 A6 2.7T 6MT and I first wanted to say that I appreciate all your help!
I'm stumped on a rough engine. I'm getting two codes: for misfire on cylinder 1 and the "random cylinder misfire". I replaced cylinder 1 with a good coil and no change. I replaced every other coil with a good one and there was no change.
I then tried unpluging each coil (1 through 6), one at a time, and each time there was no change to the rough idle (no better and no worse). I thought this was weird...
I then tried unplugging coils 2 and 3 at the same time, and the idle was rougher. I unplugged coils 5 and 6 at the same time, and the engine was just as rough as when coils 2 and 3 were rough...
I'm ruling out the ignition control module since two unplugged coils in the same bank was worse than one unplugged coil (my understanding is that the whole bank would be inactive if the ICM was bad, so two coils shouldn't make a difference). It's also not the MAF, since it makes no difference when it is unplugged.
So, I'm stumped. I'm not sure what else it could be. Both exhaust pipes smell of strong gasoline. There's very little power on the road. I should also add that the rough engine was sudden (shut off awell-running engine, got a haircut, and 30mins later it was rough on startup).
Any ideas?
I'm a long time reader, first time poster. These forums have helped me so many times with my 2000 A6 2.7T 6MT and I first wanted to say that I appreciate all your help!
I'm stumped on a rough engine. I'm getting two codes: for misfire on cylinder 1 and the "random cylinder misfire". I replaced cylinder 1 with a good coil and no change. I replaced every other coil with a good one and there was no change.
I then tried unpluging each coil (1 through 6), one at a time, and each time there was no change to the rough idle (no better and no worse). I thought this was weird...
I then tried unplugging coils 2 and 3 at the same time, and the idle was rougher. I unplugged coils 5 and 6 at the same time, and the engine was just as rough as when coils 2 and 3 were rough...
I'm ruling out the ignition control module since two unplugged coils in the same bank was worse than one unplugged coil (my understanding is that the whole bank would be inactive if the ICM was bad, so two coils shouldn't make a difference). It's also not the MAF, since it makes no difference when it is unplugged.
So, I'm stumped. I'm not sure what else it could be. Both exhaust pipes smell of strong gasoline. There's very little power on the road. I should also add that the rough engine was sudden (shut off awell-running engine, got a haircut, and 30mins later it was rough on startup).
Any ideas?
#2
May possibly be your vacuum lines:
http://www.audiforums.com/forum/audi...ey-did-133757/
Cheers,
Ray
http://www.audiforums.com/forum/audi...ey-did-133757/
Cheers,
Ray
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