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Have a friend, that has a 98 DeVille and won't run due to fuel.
He has a Manual, but nothing in his crap manual about fuel pump wiring, does have an interior lighting schematic. Worthless diagram.
Quick check on the internet, has a mention of the fuel pump relay that energises for 2 seconds, then with an oil pressure switch, and pressure it bypasses the relay and power goes to the pump. Does anyone have a diagram with the colors? (Oil pressure switch colors) Is there an Inertia switch? TX?
Check/clean the contacts to the fuel pump fuse and the fuel pump relay. Since you live in Florida, corrosion is always a major concern; therefore, I would apply dielectric grease. Both are likely located in the underhood fuse/relay box. You friend's Owner's Manual should show their locations. I'm sure there is an inertia switch, which may be located in the trunk, along the right side.
Thanks also to TX,
Looks like the fuel pump relay gets signal from PCM, then when relay is energised, it sends power to fuel pump and PCM to show computer relay is energised(fuel pump has power).
and seems that if oil sensor is involved, it is through the PCM, not inline with fuel circuit.
Thanks again to you both.
TX, Can't leave a positive, til I spread more around. Take Care.
Excellent diagrams!
You can check for power on the Gray wire at the fuel pump (tough access, but the pump's the likely culprit). I've probably done hundreds of them.
The oil pressure switch IS involved, but closes at such a low range (1-4 psi)
Linear Mode
