I can't tell you exactly what the problem. You WILL have to test when problem occurs. There is an oil pressure switch in fuel pump circuit, once you crank it enough to bring up oil pressure and the switch closes, the pump should run regardless of pump relay, that switch will not kill the pump or keep it from starting as long as the relay circuits are functional. There is also a prime connector, shows to be close to relay, passenger side firewall, it's an electrical connector, nothing plugged into it, wiring color red or possibly gray. If you use a jumper wire, run battery voltage to connector, the pump should run, use inline fuse. Did you check for codes? On some systems, the computer monitors the voltage on the fuel pump circuit, if no voltage when there should be, a code sets.
Sunday, October 11th, 2009 AT 11:09 AM