No fuel coming out of injectors

start at the beginning fuel pump pressure at the pressure regulator then look for ignition problems , check mass air flow sensor if equiped

Have you checked your fuel filter? It could be clogged. Has the truck sat for a long period of time? Is the fuel pump GM? Does it have enough fuel pressure? Are you sure it's not ignition related? Possibly an ignition module shorting out after it gets hot.

have you tried to replace your fuel injectors or your spark plugsif not try checking your fuel injectors electric socketit couid be loose

indicate excessive fuel pressure , return line blocked , inoperative pressure regulator ,problem injector seals incorrect voltage to injectors

was told it was injectors ????? We don't go by what someone told us . We use wiring diagrams , test electrical circuits using a DVOM - digital volt ohmmeter , do fuel pressure an flow testing . If you don't know how ,you should take it to a qualified repair shop that does.

Have you checked that engine oil level is okay, if so check that oil pressure switch is good. The switch is usually bypassed to start the engine, but it won't run with no oil pressure indicated...hope this helps

It idles briefly since it gets gas from your cold start valve. This means your cold start valve is good.
It dies since after that cold start valve will close as it designed that way so fuel from injectors will take over. But apparently fuel is not coming from injectors. And injectors is controlled by injector module. Injectors are normally closed until injector module tells them to open.
Check out your fuel injectors and Injector Module.
You can buy NOID from any auto part store to test your injectors. If there is no light on then there is a problem with Injector Module. If there is light on the injectors then bad injectors.
Here how NOID looks
http://www.sjdiscounttools.com/ta36330.html

Might be fuel pump, or filter is pluged up, best to chg. filter and then do a fuel pressure test.

who changed the fuel pump? no injectors on that i don't think