lift pump problems

[melbyfarms]

is there a way to test the oil pressure sending unit lift pump will run if you hookup 12 volt. Were is the power coming from is it fused to the oil pressure sending unit. What connectors should I check. Thanks Ken

[More Power]

You can connect a 12v test lamp to the lift pump electrical connector. It should light when the oil pressure switch is activated (engine idling). A lamp will load the circuit, though not as high as the lift pump, which is a better test that just measuring voltage using a DVM.

Jim

[moondoggie]

Good Day!

Be careful - my daughter's 89 (signature) was providing the LP 8-9V with the engine running - not enough for the LP to work properly. Anything other than measuring with a DVM & normal load (the LP itself) can give a false indication.

Blessings!

[Kennedy]

When all else fails, I offer a lift pump control harness that takes control of the lift pump away from the engine harness altogether for improved reliability.