i have a 2002 gmc sierra 5.3 liter ..it will start and run for about 2 minutes and then stop and not star back...i have replaced fuel pump and crank sensor and it still does the same.....need help

Is the red theft light on in the dash? Make sure it works or has it. Should come on when you first turn the key on for a second or two then go out,

yes it works

Does it go out

yes

Was this a sudden issue or did you notice a gradual downfall? You might want to swap a few relays under the hood around, if the original fuel pump went bad it may have burned the relay, I'd also check the fuel pump ground wire, should be near the pump and grounded to the frame. Sometimes there little eyelit will break off the wire

ive done all that. i checked the spark from the coil and when it starts it will fire and then it stops firing and the truck stops running and wont start back until it sets for a while

Under the hood on the passenger side there's a group of wires that run around the a/c receiver/dryer, those trucks had an issue where that wire (which gives power to coils) would rub into the dryer and short out, another place to look is the wire right out of the PCM, they rub into the control arm mount (left front near power steering pump)

checked and seemed to be all good

If you wouldn't mind, roughly where are you located