Firebird V8-305 5.0L VIN E TBI (1989)
Oil Pressure Switch (For Fuel Pump): Description and Operation
Wiring Diagram For Fuel System
As a back-up system to the fuel pump relay, the fuel pump can also be turned ON by the oil pressure switch. The oil pressure switch is a normally open
switch which closes when oil pressure reaches about 28.0 kPa (4.0 psi). If the fuel pump relay fails, the oil pressure switch will power the fuel pump.
