I have a 99 audi a4 quattro. The other day it started running rough and stuttering and my cel started blinking. I took it up the road and back and when I got back it was running fine. The next day it started doing it again and I had the cel codes pulled and it pulled p0303- cylinder 3 misfire. I replaced the coil and spark plug and got no change. I tried switching coils around and everything but the misfire stays on cylinder 3 and I have no spark at all. I was just wonderin if anyone else has had this problem and if so how'd you fix it?

 

try switching the spark plugs around, then try switching the injectors around. it could be either.

is this a 1.8 or 2.8?
is the misfire under load? at idle?

 

Ive changed around spark plugs and coils. The misfire stays on the same cylinder. It misfires while idling and under load. It's the 1.8 motor. I haven't messed with the injectors but I just can't figure out why no matter what I do I just can't get any spark at all in cylinder 3.

 

oh wait, you're sure it's a no-spark issue? as opposed to fuel/air?
If you've switch the plugs and the coils around, I would take a look at the ignition control module.

 

Yea I'm positive. No matter what coil or plug I put on cylinder 3 I can't get a spark. That's what I was thinking it could be so I ran a couple of tests on the control module yesterday and if I done them correctly then the module is not sending any power to cylinder 3. I ordered a new one so hopefully that's the problem.

 

It's a common failure, so best of luck.

 

Yea that's what ive been hearing but thank you for the help. I'll update the thread whenever I get it put on whether it was the problem or not.

 

That's been my troubleshooting process...coil packs, then plugs, and if that doesn't work it's probably the ICM

 

My ICM came in this morning so I installed it and now its running back to normal.

 

cool.