I just got a 2002 A4 3.0 Quad about 3 weeks ago with 78K. Last night the MIL came on so I got the codes read. Apparently I'm having multipule cylinder misfires, but the engine is not shaking or sputtering. Any thoughts?

 

What codes did it throw?

Could be a coilpack, or ICM, or many things, the codes will help narrow it down.

 

No ICMfor 2000+ ECU controls fireing order.
If there is a specific cylinder misfire fault code, take the coil pack on that cylinder and swap it with an other cylinder and see if the misfire follows the coil pack... If so, replace the coil pack. When your CEL/MIL came on, was it flashing? If it wasnt flashing, it may be due to something else (not a misfire) and you may have had that code storedfrom a previous time and it was never cleared. A missfire will always cause the CEL to flash. So Id go back and get rescanned to be sure there are no other codes strored.. If the engine isnt noticeably missing or sputtering, have the code cleared and see if the CEL comes back on. If the CEL does come back on, I would replace the plugs if there is no specific cylinder misfire fault code
Also, if you have multiple specific cylinder misfires, it would be unlikey that A: more than one coil pack dies at the same time, and B: more than one spark plug dies at the same time.So i would be looking into things like coil pack wireing/harness to ECU or things that could make you run rich and misfire. Of course if the plugs havent been replaced in a long time, or if you dont even know when theyve been replaced, replace them first. Geez i feel like im rambling but i just went through a misfire fiasco myself.

 

oops, yeah, 2002 no icm.

I should pay closer attention to the post.

 

dammmmnit onepoint youre always on the ball but you forgot to mention CHANGE THE MAF SENSOR!!!

I had misfire issues for a month or so...did coilpacks, plugs, 02 sensor then finally the MAF fixed it! Haven't had a problemsince!

Thats crazy,me & my mech triedfinding my ICM for hours one day and now you tell me Idon't even have one haha,nice. He saidit something the dealer covers underwarranty too up to 140,000kms due toemissions regulations here. Guess i don't need to worry about it now.

 

I wouldnt replace the MAF right away, being a $150-$300 part depending on where you get it. I think its rare to not get a lean or rich fault code if the MAF was bad or going bad. But I guess if you replace everything else, you dont have that many other choices.

 

The codes were for the 2nd, 3rd, and 4th cylinders and a multi cylinder misfire

I was driving over the weekend with plans on getting the car looked at today (monday) and the MIL turned off on its own yesterday. I'll keep an eye it. I think what might have happened was that my low oil light came on about 3 or 4 days before the MIL came on and I pulled over to add oil right away. It was dark outside so I might have put a little too much in and it could have over-flowed the filter causing the MAF to act up. I read a similar story in another post. Could this be the problem and if so should I clean the MAF or replace it?

Thanks for the help. I sleep better knowing that you guys (and gals) can help me out with my audi problems. I love this car and I can't imagine ever switching to anything else!

 

proper codes would be P0300 P0302/3/4 the highlighted one being the most important ( randomize multiple misfire ) faults listed are spark plugs, plug leads, injector(s), ignition coils, low compression, wiring

 

wtchalklat, you heard that too much oil on a K&N air filter
causes the MAF to malfunction.