I had a customer's 1994 Grand Cherokee 5.2L for 2 days with a stalling issue. He had taken it to 2 other shops with both saying fuel pump. Here is the main issue he had. Cold the engine would start and run fine. Once up to temperature it would drive along and shut off or once it was shut off it would not start up again unless you held the accelerator to the floor which once you let off the accelerator it would die completely. So at that point I though Intake Air Controller, or as Chrysler calls it Air Intake Control Motor, on the back of the throttle body. So I replaced this. Same issue. Then as I was just looking at every value I had I noticed the scanner was telling me the engine was 97*F and the gauge was reading 200*F. On this motor they are 2 separate sensors. So I replace the temperature sensor reading 97*F for the ECU and it fired right up, drove and ran beautifully.
I am posting this mainly because in my attempt to find answers EVERY single forum had listed:
Crank sensor (granted that is common)
TPS
IAC
Cam Position Sensor
Oxygen sensor
MAP sensor
and the last resort Replace the ECU
Not one had this. So I hope if anyone is having a similar issue they will get readings from all the sensors before replacing parts.
I should probably explain that the engine being at operating temperature and the ECU thinking it is still cold meant the fuel trims were all wrong sending too much fuel to the engine which stalled it out unless giving it full throttle and thereby enough air to run, but once you let off the throttle the overload of fuel would shut it off.