oil pressure switch to sending unit swap
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Car: 92 sonoma
Engine: 1985 LB9 tpi, stock
Transmission: NV3500
Axle/Gears: g80, 4.11 posi
oil pressure switch to sending unit swap
i'm trying to get my sending unit wired up and all the diagrams that i see show the 86-89 with just dummy lights. i got a gauge and i want to use it. how do i wire it up? BTW my sending unit is the one with the connector that looks like pac man with his nose and lip pierced lol
#3
Re: oil pressure switch to sending unit swap
Those engines used a "mechanical" oil pressure sending unit fed thru brass fittings to a canister type sending unit. The early version of the fuel cutoff sending unit only had 2 pins. The later ones ( 91-92 ) had 3 Pins. The 3rd pin is for the gauge wire.
I mistakenly installed a 2 pin 88 sending unit into my 91 last fall. As a result the car ran fine - but I had no reading from the gauge. Installed the 3 pin sending unit and I was good to go.
If your car doesn't have 3 wires on the plug - you could get a plug/pigtail and run your sending unit wire to it.
I mistakenly installed a 2 pin 88 sending unit into my 91 last fall. As a result the car ran fine - but I had no reading from the gauge. Installed the 3 pin sending unit and I was good to go.
If your car doesn't have 3 wires on the plug - you could get a plug/pigtail and run your sending unit wire to it.
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Car: 92 sonoma
Engine: 1985 LB9 tpi, stock
Transmission: NV3500
Axle/Gears: g80, 4.11 posi
Re: oil pressure switch to sending unit swap
ok. my sonoma has the 3 pin plug/sending unit. but i need to make sure this is still gonna run the cut off switch..
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Car: 82 Z28
Engine: 383 SP EFI/ 4150 TB
Transmission: T400
Axle/Gears: QP 9" 3.73
Re: oil pressure switch to sending unit swap
It is not a cut off switch.
It is the switch that makes the fuel pump run when cranking and a backup for the fuel pump relay.
Would be easiest to install a T at that location and run a seperate sender for the gauge
It is the switch that makes the fuel pump run when cranking and a backup for the fuel pump relay.
Would be easiest to install a T at that location and run a seperate sender for the gauge
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Car: 92 sonoma
Engine: 1985 LB9 tpi, stock
Transmission: NV3500
Axle/Gears: g80, 4.11 posi
Re: oil pressure switch to sending unit swap
so i should cut off my original fuel pump relay wires and splice in the switch? (run it like factory)?
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Car: 1986 Monte SS
Engine: 3.8 Turbo
Transmission: 200r4
Axle/Gears: 3.42
Re: oil pressure switch to sending unit swap
Don't mean to hijack the thread but I've got a question about the 3 prong plug that no one wants to answer.If I'm looking at the 3 prong plug top termanal is B(tan),bottom left(D)gray,and bottom right(C) orange.Am I correct?
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Car: 92 sonoma
Engine: 1985 LB9 tpi, stock
Transmission: NV3500
Axle/Gears: g80, 4.11 posi
Re: oil pressure switch to sending unit swap
i'm just gonna put in a new harness and splice in the old sending unit...
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Car: 1985 IROC Z
Engine: 305 TPI
Transmission: 700R4
Re: oil pressure switch to sending unit swap
i cannot get my fuel pressure relieved after pulling fuel pump fuse. wandering if i pull the power wire from my oil pressure switch, will it shut off fuel pump relay. i have read that the oil press switch doubles as a "relay" for fuel pump. any help welcome.
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Car: 87 Formula/ 00 Xtreme
Engine: TPI 305/ v6
Transmission: struggling t-5/ 4l60E
Axle/Gears: 3.08/ 3.23
Re: oil pressure switch to sending unit swap
@irocz it (OPS) is backup power to the FP, it closes at 4psi (cranking oil press).
just unplug it, start the engine and fuel pressure should drop to 0psi almost immediately. engine will die shortly after.
just unplug it, start the engine and fuel pressure should drop to 0psi almost immediately. engine will die shortly after.
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