Had problems with the idle about 2 months ago. The idle was surging to almost 2000 rpm, replaced the idle control valve after checking it by pulling the electrical connection and noticing no difference. That didn't fix it. Replaced the idle control box about 1 month ago, that fixed it, also checked the idle control valve again after replacing the idle control box and it seems to be working. Pull the electrical connection and the engine surges up to 2000 rpm. Also replaced fuel pumps, fuel pump relay, ovp, fuel distributor, fuel lines, fuel filters, and injectors, but the idle is to low and a little rough. Also, if i switch the a/c on, the idle smooths out and you dont even know the car is running. I've checked all the vacuum lines, injector seals (brake cleaner test) and cannot find anything out of place or any leaks. The engine runs excellent otherwise, great accelleration, smooth when driving at any speed, no problems at all, just this pesky shake on idle. Any suggestions would be great!