Well ive been having this problem for a while now. Sometimes when u first start the car is idles rough and the rpm go's down to 400. I had a performance exhaust put on and a set of msd coil packs, well me and my dad thought it was the cat converter clogged so we cut it off, well that didn't take care of it. Me and my dad think are timing could be off because we put msd coil packs on the car, so maybe the timing is off? The check engine light comes on and it idles rough and misses. Also but everything is fine after the car is warmed up so we don't get it. Maybe a o2 Sensor? The car is a 1991 L.X 2.3 , any help would be great!
The ICM controls the output to the tach. Mine was dropping RPM's and even dying when the Check Engine light came on. If you do a search on ICM you should be able to find my last post and a few others that have had the same problems. Good Luck.
