1994 Chevy 1500 engine dies?

I have a 1994 Chevy 1500 2wd, 5.7 liter, only when the temperature outside is warm the engine will shut off at random times, after it dies, it might crank up but only run for a split second, after about 15 minutes of doing this the truck will crank up and go.

I have changed the fuel filter, pcv valve, and fuel pump relay, cleaned the distributer cap.

For some reason I think it might be in the wiring, but may be wrong,

Any help is greatly appreciated,

Thanks