Did the ignition control module coolant temp sensor and plugs last summer. Was getting on the gas a bit today, and the car started missing. I babied it home, and listened to it in the driveway.

I heard it knocking at idle, its rough, and codes were as followed:

16684 - Random/Multiple Cylinder Misfire Detected
P0300 - 35-10 - - - Intermittent
16688 - Cylinder 4 Misfire Detected
P0304 - 35-10 - - - Intermittent
16686 - Cylinder 2 Misfire Detected
P0302 - 35-10 - - - Intermittent
16684 - Random/Multiple Cylinder Misfire Detected
P0300 - 35-00 - -
16688 - Cylinder 4 Misfire Detected
P0304 - 35-00 - -
16685 - Cylinder 1 Misfire Detected
P0301 - 35-10 - - - Intermittent
16685 - Cylinder 1 Misfire Detected
P0301 - 35-00 - -
16687 - Cylinder 3 Misfire Detected
P0303 - 35-10 - - - Intermittent
16686 - Cylinder 2 Misfire Detected
P0302 - 35-00 - -

I just did both motor mounts last week but havent had issues.

When I was driving home, the CEL would blink and it would be rough, then stop blinking and it would be fine.

Ideas? Thanks!

 

Go back and look at those connectors on the ICM and coils. If they are good you might have a bad ICM. Was it aftermarket, auto store cheapie, or OEM?

 

Checked the connectors on the ICM, even plugged the old bad one back in. The ICM was replaced with a HUCO one. Only reason I'm curious is because I never knew an ICM could fail and misfire all cylinders, I thought it would do one. (thats what the old one did)

 

when its on its way out, normally cyl #2 starts misfiring first but if it dies completely all of them start.

 

Got a new one for pretty much cost +tax at the local shop, came out to like 75 bucks, installed it, and seems good. I think this issue had something to do with the thermal paste used that when everything heated up and fried the HUCO. When it started missing at first it was when the car was hot and I was banging through the gears at high RPMs. Used a better paste and we'll see what happens.

 

i did this
http://www.audizine.com/forum/showthread.php?t=292631

the ICM normally sits in the airbox and has a ton of airflow over the little heatsink on the bottom of it. when i removed the heatsink, you are right, the thermal paste wasnt very good and the two contact sides were far from flat and did not make complete contact. and if you use a cone filter and remove the ICM from the flow of air, it gets real hot.

 

Thanks for that. I had some arctic silver thermal paste lying around and I used that so I would imagine it would do the trick.

For whatever reason after the misfires and the codes, the car isn't boosting up to its 12 psi anymore. If i can get it up to 10, im lucky. Any reason why its doing this? Maybe the ecu needs to readjust itself?

Thanks!

 

I thought I read where the boost is limited after sever mis-fire until you vag-com it...?

 

I do have vag and I cleared the codes