I have a 93 Cav with a 3.1. I was having Idle problems, every time Id come to a stop the idle would bounce and then either stall or vary up and down. I took out the iac and cleaned it also cleaned the throttle body the car ran great a month later the problem was back but nothing was dirty. So I replaced the IAC 2 days ago and the car ran like new, today it stalled pulling out of the drive way, then in traffic the idle dropped down to about 600 rpm then surged to 1500, I put the car in neutral and it jumped to 2200 for about 5 seconds then it fell back down to about 1000. It also chugs at idle almost like an old big block Chevy, smells incredibly rich. I tried the idle relearn procedure that didnt work, I checked for vacuum leaks and found nothing. What should try?
Fuel pump probably? Sounds similar to what my car was doing a year ago. This was an on going problem for 2 years and no one could figure it out until I took it to the right shop.
