I have a gen 5 502 and last week when I turn the key one click u can hear a click at the tank but the pump does not turn on. So I went and bought a brand new pump for it. I went out yesterday and after driving for 45 min it went out again and again will not turn on. I looked over the wiring and it all looks ok, any ideas ? Did I really blow another one? Any thoughts of why this is happening? Thankyou

Basic VST operation-
Key on, ecm energized, fuel pump relay closes for approx 2 secs or until oil pressure is reached.

I'd be looking at my relay.

Agree, check relay. You could also swap the two relays, one is for main power the other is the fuel pump, and they are both the same type. Should be side by side

Thanks guys that was it!!