Hello,

To start it off:
1998 Audi A6Q 2.8l
5-speed Tiptronic
All oil and typical maintenance done by me and my wife every 2,500 miles, Since recently found that my local german/import dealer were screwing military/serviceman over outrageously(Everything around here tends to do that.)


Recently(Last week) I had to have my Flex pipe on right side replaced. After being replaced, car ran GOLDEN. Never has ran so smooth in the 5 years I owned it. Drove it for two days perfectly this exact way.

The next morning I wake up to the car Starting, rough idling for 2-10 seconds and stalling. Frustrated, I grabbed the Code-reader, ran through got two codes(Both emissions) and reset my codes. Started her back up and she actually continued to run, with rough idling, but stayed running. After checking my codes again I didn't get emissions but instead an airflow error. Checked out my intake and decided to clean out my MAF and complete intake.

After letting my intake dry out, Put it all back together, and started her up again, this time the engine was really out of balance, feeling as if it was misfiring. Would feel as if a few misfires every cycle. If pressure applied to accelerator, my RPM's actually would drop.(800ish- dropping almost to 100), and after a code read I got p0300, p0301, p0302, p0304 which I know is 1, 2, 4th cylinder misfiring. I actually had this problem about 3 years ago, and after hard resetting the car, It fixed itself, but not the case this time.

I am figuring on doing a completely clean swap of spark plugs tomorrow to see if it helps any, But wondering if anyone has an idea if its anything in particular that they know of. I leave for afghanistan in about 2 weeks and trying to get this problem out of the way -_-

Any help would be GREATLY appreciated

 

seems like you are on the right track

I'm guessing the ignition coil (search)

 

It not likly that you have 3 bad ignition coils. What i would do is mark all the coils with there cylinder & swap with other cylinders , reset faults & see if the faults follow the coils or do they stay at the same cylinders. If they stay at the same cylinders , try the same thing with the plugs.

You might as well just empty your wallet on the ground if you just throw parts at your car blindly.

 

^^^^

the 30V 2.8 does not have individual coil packs like you are thinking.

there one ignition coil set per bank. three ignition wires per bank.

 

Sorry , used to working on later cars. I would still try to swap wires & plugs.

I see all to often people just thowing parts at cars trying to fix a problem when some simple elimination would save them money & trouble.

 

True enough but in this case plug swapping is worth it. Plugs are cheap and a good idea if they haven't been changed and/or gapped in awhile.

 

Ok, so an update.

I just switched out my spark plugs and wires, and starting her up....running perfectly. I checked everythign over and seems to be in balance now, and no more misfire codes. get in for a test drive, throw it in reverse and SLAM. try drive...SLAM. put in it park....smooth as can be. After a lap around the neighborhood, it seems as though its in 3-4th gear. typical rpm, but acceleration is that of a snail. feels like its starting in third, and never shifts(It doesnt shift while driving now).

I never had this before changing the spark plugs, what would set it off now?

 

sounds like limp mode

you will need a vag-com to see if it is throwing any transmission codes

 

Ok, So *facepalm* after inspecting again, my MAF needed unplugged and plugged in again and the tranny is now working fine.

Quick question though, My car has a CAI(was not put in by me, but previous owner, so I do not have original intake). But has a fairly rough idle which I believe to be due to the CAI. because as soon as MAF is unplugged...runs smooth as silk, plug it in again and starts idling rough. sometimes even wants to/does stall. Which i think is from too much Oxygen to fuel ratio.(My only conclussion) Is there anything I can do to allow it to mix better etc? I do not get any codes from it actually for once I have 0 codes lol.

BTW MAF was just cleaned 2 days ago with CRC. and looks to be decent.

 

Your MAF could be shot. Ditch the CAI, the audi box is as good as it gets anyway.

You can test the MAF if you have a vag-com.

After the car warms up, do the issues seem to disappear or lessen?