So like the titles says its a 97 a4 1.8tq with 180k. Today randomly it started running like a flat 4 (sound). I was guessing misfiring, coil pack, or the plug. I replaced the coil packs around 10,000 miles ago, I also saved the original coil packs numbered by cylinder. The code came up PO302 so cylinder misfire on #2. So I pulled the coil off and switched it out with all the old coil packs (tried them 1 at a time to see if it was the coil pack) no improvement. I started the engine again and pulled out #2 pack and it ran exactly the same...so not getting spark to #2. Pulled the plug and checked gap...within the norm..it did have some heat stress (rainbow swirl on the metal) and there was a bit of black carbon and the spark tip was brown. I cleaned it up and reinstalled. Pulled the battery and checked the voltage...it was good 12.6v, cleaned all the terminals, reinstalled.

The only odd thing was when i took it to the auto parts store to get it scanned he could not reset the codes...he said the obd2 scanner could not reset it????

Also there was a PH76 code I could not find info on the description was: manufacturer specific power train.

Any Ideas....I'm probably gonna have to take it to the shop on Monday.


Thanks,

Aaron S

 

bad icm, or wire to #2 coil pack.

 

Yeah, most likely a bad ICM.

 

Just another quick question. Would the car being chipped prevent the obd2 scanner from resetting the fault codes. I'm gonna look into the icm, i did't see any frayed wires on the coil pack harness.

Thanks for the info, very much appreciated

Aaron S.