Sierra Starting Problems

[207GT04]

My father drives a 2004 4.3L Vortech Sierra. The truck stalls and will not restart. Occasionally after sitting for several hours the truck may restart. On an occasion in which is has not restarted dealer replaced the fuel pump. The second occasion the dealer replaced the ignition switch. It cranks but will not fire. Thanks for help if any given and if its not fixed soon they will be buying a toyota or nissan so someone better help for GMs sake.

[ChevyTech007]

Thats a tough one without anymore info but here goes nothing. First check would be the dist. cap and rotor and coil wire. I have seen a bunch cause this. If it is a no fuel concern the fuel pump relay is a possibility but the best choice would be the whole UBEC. I have seen loose terminals cause this and there is no way to repair it, the entire UBEC (relay center) has to be replaced. Just 2 cents worth.

[Draenor]

I have had this happen lately. After the hurricanes down here in LA, some of these gas stations got some crud in there tanks. You could of gotten some dirty fuel. You might want to change the fuel filter. It was a $10 fix....hope it helps