Ok so i have a 94 accord and my idle surges only at a stop and its driving me nuts, it only does it when its cold outside, ive tried two different iacv valves fast idle thermal valves ive cleaned them and nothing helps, i had the timing belt,water pump, and radiotor done recently so i no its not a coolant problem, but it does have an aftermarket intake and i noticed whoever put it on removed the iar but left the solenoid, does anyone have a clue ecu maybe?

 

Bleed out the air in the system and replace your thermostat you have checked the other recomendations.

 

like i said ijust had the radiator and water pump replaced by honda so i dnt think it needs bled out but ill give it a shot, but why a thermostat?

 

Check that PCV is checking air flow. If PCV is stuck open, this can cause a loping idle.

good luck