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98A4TQ
05-13-2008, 06:58 PM
when i got my car 98 A4TQ it had 103000 on it at 105000 the car threw a P0402(cylinder 2 misfire) the car ran like complete crap. Then about 2 hrs later the problem completely stopped and the car ran great again. So I brushed off the problem . Then saturday 2.5 years and 24,000 miles later it happened again P0402 this time it lasted for 2 days. Now its running completly fine again. Cleared the code and nothing came back since. I havent done anything recently to the car except 1000 miles ago changed the air filter and cleaned the MAF with MAF cleaner spray. I just cant see the coil pack or the ignition control module being shot cause its running fine now. Does anyone think it could be a bad wire somewhere or a randomly sticky injector on cylinder 2. I would swap coil packs around but because its not misfiring now I dont think I would get any info from that. Any info would help .

Rico750
05-13-2008, 07:13 PM
when i got my car 98 A4TQ it had 103000 on it at 105000 the car threw a P0402(cylinder 2 misfire) the car ran like complete crap. Then about 2 hrs later the problem completely stopped and the car ran great again. So I brushed off the problem . Then saturday 2.5 years and 24,000 miles later it happened again P0402 this time it lasted for 2 days. Now its running completly fine again. Cleared the code and nothing came back since. I havent done anything recently to the car except 1000 miles ago changed the air filter and cleaned the MAF with MAF cleaner spray. I just cant see the coil pack or the ignition control module being shot cause its running fine now. Does anyone think it could be a bad wire somewhere or a randomly sticky injector on cylinder 2. I would swap coil packs around but because its not misfiring now I dont think I would get any info from that. Any info would help .

swapping the coils around might be not a bad idea. I had this happen once with bad gas. (it then not came back only if i got gas at this one certain place) It wouldn't surprise me with todays gas issues that the quality of gas [down] goes down.. did you get good quality gas?

maybe bad spark plug could be too... check the gap also.

98A4TQ
05-13-2008, 07:38 PM
I always get my 93 oct at the same place,maybe they had a bad batch though, but wouldnt bad gas cause problems in all cylinders. I was gonna check the plugs too but now its running completly fine. I have to look for a short in the wiring going to the coil pack. Does anyone agree?

98A4TQ
05-15-2008, 07:16 PM
i ordered a new ingition control module , 4 coil packs, and new spark plugs. We'll see if that works.

98A4TQ
05-19-2008, 07:46 PM
got the plugs,coil packs and ICM today. I installed the plugs and coil packs first and still had a cylinder 2 misfire. So i threw in the ICM and shes running like new.