wisconsin_quat

After recently fixing my seized windshield wiper linkage, I have a strange misfire only at cylinder number 2. Here is the background on the situation:

- (2 months ago) Fixed wiper linkage, in doing so you have to remove the cover for the ECU compartment. I decided to remove the ECU as well and take a look inside to see if it was a stock ECU. Immediately after fixing the wiper linkage and reconnecting the ECU and buttoning up the job, the car was began running rough as I pulled it out of the garage. I pulled it back in and removed and reconnected the ECU. Fire it up and no issues.

- (2 weeks ago) Car began misfiring amid an afternoon commute. Swapped ignition coil on cylinder 2 but no change. Came home, unplugged the ECU, looked at the connections, used contact cleaner on ECU pins, put it all back together and it runs perfect.

- (today) on the way in to work unfortunately, car began misfiring again. I have a dinner date tonight and need to fix this asap... any thoughts on the culprit?

Tgr_Clw

Any codes?

x1rider

after getting my ECU re-flashed with the 2nd version of the GIAC program, GIAC recommended that a throttle body adaptation be performed after reconnecting the ECU. I don't know if not doing it would cause misfires but it wouldn't hurt to try.

wisconsin_quat

PDX04a4, after reading your post on the ignition problem, I think we have the same problem. No spark at coil #2. My problem is intermittent however. I have isolated it to a bad connection at the ECU harness to the ECU. Either that or there is a frayed or separated wire somewhere under the ECU cover in one of the harnesses that when moved around effects the connection. Based on my post what are your thoughts and are you going to go ahead with the same plan of attack on your repair or are you thinking about narrowing it down? When I get a chance I'm going to slice back the housing on the wire harnesses and look for a frayed wire... If no luck with that I will either have to pin by pin check how firm the connection is in each slot in the wire harnesses to the ECU. Next I will look at the relay connections and the relay itself. Here is the original post from 6/26/08:<ul><li><a href="https://forums.audiworld.com/a4gen2/msgs/1104798.phtml">https://forums.audiworld.com/a4gen2/msgs/1104798.phtml</a</li></ul>

wisconsin_quat

Will let you know shortly...

wisconsin_quat

unplugging #2 and reconnecting #2 = no issue any longer...<ul><li><a href="https://forums.audiworld.com/a4gen2/msgs/1068561.phtml">https://forums.audiworld.com/a4gen2/msgs/1068561.phtml</a</li></ul>