Truck Repair: 1992 C1500 Chevy Truck 350ci, air control valve, chevy truck

Question
Would like to know if anyone could tell me why my truck will not stay running. It will start and run for a few minutes and then cut off (like it's out of gas), but if I start it and keep my foot on the gas at a steady idle it stays running. Is this a fuel pump problem? I have replaced the fuel filter, cleaned the fuel injectors and checked the computer. Computer gives code 12 which is all clear. Or is this some kind of sensor? Any help would be great.

Answer
I would suspect the idle air control valve on the throttle body.
You can clean it with carb cleaner, on the truck.
It is also possible your egr valve is opening for some reason while idling. It shouldn't.

I would probably connect a fuel pressure tester, and watch to see if the pressure drops before it dies, or after it dies. It shouldn't drop till After the engine dies.

Van