I have 1999 Chevy Tahoe starts fine cold after warms up shut it off go in store come out starts then dies let it set 15 or 20 min it will starts fine .replaced fuel pump regatlor spiter injectors coil tuned it up and replaced fuel filter only thing i havent replaced ightion modgel.

 

put a fuel pressure tester on the fuel system and see if it leaking down. If it doesn't...you have rulled out the fuel system and can focus on the ignition system

 

Harold Cross: Welcome to the forum.

Good advice above. Always good idea to take measurements such as voltage and pressure before throwing parts at the problem.

FWIW, you can pick up a fuel pressure tester at Harbor Freight for around $25.00.

 

I know this is a rudimentary question, but does it over heat?
did you remove the thermostat?