So I was dealing with an issue where my 92 Dakota 3.9l was overheating and finally got it figured out. Now when I ran the truck to idle checking to see if it overheated again I let it idle for about 5 minutes. When I put it in gear to pull it up in the driveway it stalled and will not start up again. Any ideas?

 

Update: Gave it 20 minutes and started right up. Pulled it into the drive and it dipped in rpms real quick, then back to normal but never stalled. Still not idling totally normal though. IAC maybe?

 

I would say that it's a sensor. Check your codes - with OBD1, I found that not all malfunctions were picked up the way they're supposed to, so some were stored without the check engine light, and some just happened with no indicator at all. If there are any codes stored, they might be able to give you a better idea of what's wrong.

I had a couple of jeeps with OBD1 (still have 1 of them), I would get similar symptoms as you're describing when the Throttle Position Sensor malfunctioned - there were other symptoms, but in all cases, everything would work until things started to warm up & then, I'd get really rough running and slowing to the point of stalling - then you couldn't start it until it cooled.

If you're lucky enough to know someone with a similar engine, you could borrow their TPS to see if this is the case(before you buy a new one), otherwise, this is what I'd focus on if it were my truck.

If you choose to play around with the IAC (this is a stepper motor, not really a sensor), be careful not to pull the plunger out. If you do, you will have destroyed the unit.

 

All is fine. When I was dealing with the overheating there is a plug connection right next to the thermostat housing. It got disconnected when I took off the thermostat housing. Cleaned the aic and housing and runs fine now. Ran all day with no problems. If it happens again I will be replacing the tps and aic. Thanks for the info. As always greatly appreciated. I can fix anything, but not the greatest at diagnosing.