Fuel Pump Not Priming

[RLC]

If your problem returns it might be your fuel pump. I had this same issue on my 2001 Silverado 5.3. It would not start after the vehicle set for over a couple hours. I would cycle the switch on/off three or four times and it would start fine. I am not sure of the exact pressure, but the fuel system should retain some pressure when it sets. I checked my fuel pressure after the truck set for a few hours and it would drop down to nothing. It was the fuel pump; replaced it and no more issues.