1994 Stock LT1 A4 94,000 - did a 90 k tuneup with new opti, plugs, wires.

Another 4k after the tuneup it started running like this. I did a couple free scan logs if anyone wants to see them, but the only thing that looks out of the ordinary is the spark advance at 40-43 under acceleration. And the o2 reading well below .500.

It throws codes 36 and 42. Takes about a good 15 - 20 minutes of driving after resetting computer for it to start missing bad, sputtering, won't pick up RPMs under full or partial throttle. Runs like a dream before the missing and sputtering, but we had to limp home at 1200 rpms last night after it started.

Guessing ignition related, mainly the ignition control module.

Any other thoughts?

 

i was gettign codes like this after my tuneup, turned out to be the coil wire not clicked in properly on the opti