If you jumped the pump to run off battery voltage and it runs fine, then the pump is OK.
The problem lies in the pump wiring harness, or oil pressure sending unit which serves as a backup to the FP relay.
The oil pump sending unit is designed as a backup to FP relay, but not designed to run pump all the time.
I would replace the OP sender, if problem persists, then you will have to get into the harness and check for open/shorted wires.
Wednesday, July 22nd, 2009 AT 8:05 AM