I have a 1998 GMC sierra 5.7L V8 vortec and I'm having fuel issues. My truck will fire up and I can drive it for about 25 min or so then my truck will shut down due to no fuel. If I try to restart it, it will turn over but not fire up. After it cools down my truck will start up and work fine again. I've replaced the fuel relay and the fuel pump wiring harness. I have not changed the fuel pump because i can hear it trying to run when my truck starts acting up. Does anyone have any ideas? Thanks for the help.

 

it is possible that the fuel pump is the problem as i have had them stop pumping the proper pressure. It was on a 1994 suburban and the truck would run but max throttle was like 3000 rpm and no better then about 35mph. changed the fuel pump and voila all goooood.

J

 

Check your fuel pressure...just because it is running doesn't mean it's giving you enough pressure. Those motors are also famous for the spider injection going bad.

 

i am thinking now it is not my fuel pump. my truck will turn on, idle and even drive for about 15min to twenty min just fine. it seems on a hotter day or when the engine gets hot (does not over heat) the truck stops. even if i let the truck idle whatever is wrong with it will still fail. once it fails the engine will turn but not fire. once the engine cools down completely it will start up again and again run fine with no indication of there ever being a problem. i was thinking it was the fuel pressure regulator. just a thought.