Why is my Jeep stalling?

I have a 89 cherokee Laredo 4.0L. My jeep stalls 99% of the time when it gets around 210f by the guage. 1% when cold. It does not matter if its at idle, speeding up or slowing down. I had a dealer check it. They claim it lost fuel pressure and was low to begin with.I replaced the pump & strainer per dealer and no change at all. I have replaced the MAP, ICM, cap & rotor, plugs, Crank sensor, and a broken pre-heater hose. Still stalls. About a year earlier I replace the serpentine belt but I was running fine before and after that. I drove it in a couple miles on a broke belt but it did not have time to get hot before it got home. It seems to be related to the engine temp more than anything. If it cuts off I can crank the engine and after a few tries it starts and will run till it gets about the same temp again. It may take a 2-15 mins but it wil restart. Its got the old AMC computer in it and to be honest I dont think any of the several mechanics or the dealer may be reading any codes. I cleaned the Idle control and no change. What could cause these symptoms at Idle, while speeding up, and slowing down? From my own work around transformers I am starting to think maybe a sensor or the coil. I have seen coils (non-auto) that would work get till they ran awile then stop working for a few seconds to a minute or a hour then work again. This might account for when I tested it a few time it was getting spark to the plugs right after the stall. Up till this started the jeep ran great. Thanks for any help you can give.