I just got done taking my engine out of my car and replacing the main bearings and rod bearings. Put it all back together and the car was very tough to start and after it finally started was running very rough. CEL light was on and read three codes. Random misfires detected, misfire in cylinder 1, and misfire in cylinder 2.
things ive already tried to fix it: brand new spark plugs, swapped the coils out with the two cylinders that weren't misfiring, swapped the injectors with the two that weren't misfiring. Then unplugged the 02 sensor, ran the code and got the o2 sensor code and plugged it back in and the code went away. Did this to both o2 sensors individually. Should rule out o2 sensors right?

Thats all I've tried so far. Need help so I can finally finish my car that has taken all summer long to do. Thanks

 

ICM maybe? I had a horrible misfire on Cylinder 2 (most common cyl to go bad when ICM is on the fritz)...

 

I actually don't have an ICM. That's the one that attaches to the top of the air box? because I have an empty slot there and noticed it when taking my engine out and everything. Never had anything there.

 

you're right. My bad, I think after 99.5, they did away with the ICM all together. You may have a short or cut in your wiring harness...?

 

If his car is 2000 and up it no longer has an ICM. What was the result when you swapped coils?

Because it will sill misfire if you have a bad coil it will just be on a different cylinder.

So if you had misses on 1 and 2 it should then be on 3 and 4

Jason

 

THe misfire did not move to the other cylinders. Sorry forgot to mention that. And its a 2000. So I guess that's why I don't have one. But its weird that they still have the slot for it on top of the airbox.

However, now we are thinking that maybe my computer needs to be reset since the battery was unplugged for so long (3 months). Is this a possibility?

 

After much research, I decided to try and change out the coil pack wiring harness. I hear this part goes out a lot due to poor wires and removing the engine and putting it back in could've damaged it also.

Since they don't make one that is "Audi" verified, you have to use the one they make for the VW 1.8t. ECS tuning was sold out until October 5th, but they have it for the best price, $50 free shipping.

I wanted mine now so the ONLY other place I could find this one was here Coil Pack Wiring Harness Replacement, Mk4 Unfortunately $75 after shipping.

Will update status after replacement