I have a stock 1988 iroc 305 automatic i can not get the car to idle at 750 or anything below 1000 rpm. I have replaced fuel regulator, fuel pump, fuel filter, iac twice, maf twice,coolant temp sensor twice,tps,02 sensor,plugs wires cap and button. The car start and idles around 1300-1400 then drops to 1000. I have tired base idle reset,iac reset. I also connected a fogger to the vacuum and had no leaks besides a very small leak on the throttle cable side of the throttle body rode.It's base timing is at 6 degrees and when wire plugged back up it goes to 30 degrees at idle.

The readings on all the sensors at idle is:
Rpm: 1000
tps: .51
iac: 2.0
coolant temp: 177
maf: 10.51
02: 839.16
I feel like I have tired everything besides a new ecu and prom but i dont want to waste any more money by just throwing parts at it, and I don't want to drive the car because it jerks when put in gear. Please help!!!

 

iac count is 2 ?? Maf gps seems high

 

It was at 2 the longest but honestly it's all over hopefully this helps.

 

Very hard to interpret, if your at 2 you have a vacuum leak or the throttle blades are open to much. I’m surprised it’s not at zero trying to get target rpm.

 

I have done a base idle reset so the blade should be closed with a 750 idle. I also tested for vacuum leaks and only found a very very small one I don't see how it could raise my rpm by 250.also should the timing advance to 30 degrees at idle which wire plugged in?

 

you followed the fsm and were able to get 5-550 rpm with iac unplugged? Depending on lv8 (refers to Load Variable 8 cylinder)you will see timing over 20 with est plugged in.