Engine Low Oil Level Sensor Wiring

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Sorry should've mentioned this:
Its a 4cyl car which has been v8 swapped. I'm using aftermarket fuel injection, and the factory wiring is all over the place. Do you know what color the wire is and where it goes from the harness?
 
Not sure about the 4cyl wiring but my 89 is dark blue/lite green stripe? Don't know if they changed wiring color and/or wire harness location for your year 4cyl or if the 4cyl model even had a low fluid module.
 
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The wire goes into the O2 harness. White with pink stripe

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Do you have the ECU harness still in the car? I have the Ford wiring diagrams for my 93 but I need to know where to start looking i.e. where the HEGO harness plugs into the ECU harness or where it is picked up under the dash.
 
Curiosity got the best of me so I traced it down. The wire on a 5.0 car is a 20 ga W-PK wire and is #258 it runs to connector 12A581 (ECU harness connector for the HEGO harness) to connector 14401. From there is runs over to the low oil warning relay.

On the 4 cylinder cars this wire does not exist. Copnnector 12A581 is missing the W-PK wire.
 
Does this mean the 4 cyl cars have no provisions for low oil circuit?
If your car does not possess the trouble display with the low oil light then it is probably not provisioned. You could certainly install one. Pretty sure it's two wires and a light bulb hooked in series with the oil pan switch.


If you don't even have the light silhouette in the dash then use some cool like this


:rock:
 
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The 4cyl cars did not get one, but if the car was V8 swapped the wiring may be present. The dash harness for the 4cyl and v8 is the same, and the v8 engine harness will contain the white/pink wire. You will likely find the white/pink wire in the engine side of the harness where the o2 sensor harness plugs in if it's not present on the o2 harness.

From there, it runs under the dash to the low oil relay. This won't be present on a 4cyl so it's a loose plug hanging just above the clutch pedal. You can test continuity from the white/pink wire there to the one in the engine bay to see if it's continuous. There are two white/pink wires. One comes from the igntion and the other goes to the sensor.
 
The wiring diagram for my 93 shows the wire is not there so I would be curious to know if it is actually there or not. However my curosity is not high enough for me to go chase it on my car and its about 29 degrees so not going in the garage today.
 
You can add the circuit to the loom into the processor, and if the instrument cluster has a low oil light provision on the printed circuit, it might just work.
Back in the old days the take outs were there (fog lights and such), so you could just add things
You might just find that wire in the loom somewhere just dead ended
 
Ok so the wire going to the rear of my gauge cluster is present. It is a small, solid grey wire. My gauge cluster itself has the cutout that says check oil, but it has no bulb in it. I can't find where this wire goes under the hood.
 
did you check the o2 harness where it plugs into the engine side of the harness? The wire should be present there on a v8 engine harness.

From there I believe it goes through the pass side firewall.