1990 Chevy Truck 1990 Chevrolet C1500 -- Engine Stalling!

1990 Chevrolet C1500 -- 350 V8 TBI -- Regular Cab, Short Bed, 2 wheel drive, 89000 miles.

Everything on truck is 19 years old, except:

New parts: EGR valve, coolant temperature sensor, fuel filter, idle air control valve, pcv valve, air filter, 1 oxygen sensor (in the exhaust manifold), spark plugs, distributor cap and rotor.

Hello there,

My truck's compression is good and I do get spark.

I have driven it once where the check engine light stayed on while driving at speeds of 60 mph on highway. Turned off the engine and turned the engine back on. The check engine light did not come back on. I hooked up the Actron CP9001 code scanner.I received: Flash (pause) Flash Flash. That means I got a code 12. Six times. This means system is normal.

On cold starts, most of the time, engine starts right up. My engine runs strong while accelerating and driving. When it gets to operating temperature and I stop at a stop sign, truck shuts right off with all the dash lights still on. (The check gauges, check engine, and battery lights are still on.) I try to start the engine, the engine cranks over strong, but engine does not start.

I let the truck sit until engine is cool and I try to restart it. Sometimes it restarts, sometimes it just cranks over.

I checked around throttle body, pushed the throttle, and no fuel was coming out. Bone dry. However, if I let the truck sit and I jump start the truck, the truck cranks over strong for a little bit, but has always started right up. It will only drive so far and after I stop the truck a few times at a few stop signs -- it will stall again at idle.

Fuel pump comes on. (I hear the whirring sound when key is in the "ON" position.)

Is the fuel pump weak at idle? Or could it be the ECM/PCM? Or both?

Thank you!