Ok so i was getting a code for a cam sensor. Which i replaced and when i did i noticed my pump was not priming at startup. Thw truck cranks then i stop and then it fires up the second time. Thw truck runs fine after that. The pressure is fine aslo. I do have a secondary pump in line hooked up to a hobbs switch. To be fair i had a short in my harness which i believe believe i found.

Things i have tried. Swapped relays no luck. I checked grounds. I looked over the harness. I wiggled the wires at the tank. I even tried manually priming the pump. And that doesn't work either which is weird to me. The pump is working but it has a hard time starting up until it builds pressure.

All my searches lead me to people whos engines do not run. Mine runs fine. Could the pump be going or is this an electric gremlin?

Thanks in advance for looking

 

Have you checked for gas inside the fuel pressure regulator vacuum line? If the diaphragm is bad it'll cause the exact symptoms you describe on a return type system.