Mechanics

FUEL PUMP POWER

1991 Oldsmobile Cutlass

Electrical problem
1991 Oldsmobile Cutlass 6 cyl Front Wheel Drive Automatic 78,000 miles

Hi I am having an issue with the power to the fuel pump in this car. When you first turn the key on and the pump should run for a fdew seconds to prime it doesn't, but when you crank the motor it comes on but the motor didn't get it's prime first so it takes alot of cranking to start. So I guess I need to know what powers the fuel pump for the first few seconds?
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Sjf1075
February 26, 2010.



Hi, I'm not sure which Cutlass you have, there are several? The initial prime comes through the fuel pump relay. Some systems have an oil pressure switch in the fuel pump circuit, just a redundant power supply to the pump, wired in parallel to the relay. Once you crank it enough to raise oil pressure, the switch closes and the pump will run, even without the relay. You may need to check circuits at the fuel pump relay, with extended crank.

JDL
Feb 26, 2010.