When the engine starts to warm up, it stalls, stops idling?

The car had no spark and we could not get the ignition module. The car was parked for 4 months, then I bought an aftermarket distributor. Then the car idled fine when cold, but when it starts to be warm it stalls, stops idling. I tested the IAC valve outside the car, and it passed those tests. Tested while on connected on the car but not connected on the throttle body, i.E. Closed the bypass hole and closed the other whole with a finger. I watched the IAC closing slowly as the engine warmed up, because I was controlling the air with my hand. It continued idling higher as the finger cannot control the pressure the engine is pulling the air. I also tested the MAP sensor, it is fine. I also tested the TPS, it is fine. There are no vacuum leaks. What could be the problem here? The car only drives when you adjust the idling higher through the throttle stop screw.