Idle problem

[summervette]

i have a 91 coupe and it has a idleing problem after you start it and drive it for 30 to 40 min. it starts to idle bad the temp is high 230 degrees. the rpm go from 800 to 4oo,500, then it stalls, and you have to restart,it start s okay. When you drive on highway or over 30 or 40 no problem. slower speeds is when this happen it stop lights. I have had 8 new injectors installed, new fan ,rebuilt ecm, erg valve, plugs, wires,pvc, etc.

 

[c4ever]

I would start with a throttle body cleaning, set TPS, IAC and idle adjust per the manual. I had the same problem and that was the fix for me.
Carlo