Non Locost Issue

[dagr8tim]

I know this doesn't apply to a Locost build, but I'm running into an issue that I'm hoping somebody has some insight into.

I'm working on my daily beater (93 Cutlass Ciera with the 3300 engine). I was at the junk yard on Friday and I found a sport model with a full gauge cluster. I snagged it and put it in without issue. All of the gauges work great with the exception of the oil pressure gauge.

After getting the cluster in, I realized that I was pegging the oil pressure needle. Alittle research showed that I needed a pressure switch (sending unit) from a car with the gauge and not the idiot light. 93 didn't offer a full gauge cluster in my car. So I snagged a sending unit that fit an 89-92. With that sending unit, the gauge sits at 80 psi, and goes up slightly when I drive.

After a bit more research, I realized that my car uses a 4 wire plug on the sending unit & the sending unit for 89-92 is a 3 terminal setup. I also found out that a 91 Bonneville with the oil gauge has a 4 wire setup. I tried one of these sensors and got nothing. I'm trying to bodge together a sensor setup that will drive the gauge.

Does anyone have any remote experience with GM factory gauges that can help me sort this out?

[Miatav8,MstrASE,A&P,F]

On the earlier models, an oil pressure switch keeps the fuel pump on after engine start. The idea was to save the engine if oil pressure is lost.


Oil pressure fuel pump control (usually 2 wires).
A oil pressure switch is used with an idiot light (usually 1 wire).
A oil pressure sensor is used with a real guage (usually 1 wire).
Sometimes, there is a ground wire in addition to ground through the threads.

You need to use the sensor for the cluster, then rewire/plumb as necessary.

[dagr8tim]

On the earlier models, an oil pressure switch keeps the fuel pump on after engine start. The idea was to save the engine if oil pressure is lost.


Oil pressure fuel pump control (usually 2 wires).
A oil pressure switch is used with an idiot light (usually 1 wire).
A oil pressure sensor is used with a real guage (usually 1 wire).
Sometimes, there is a ground wire in addition to ground through the threads.

You need to use the sensor for the cluster, then rewire/plumb as necessary.

Thanks for the info, the first sensor I tried was a new one that was supposed to be the same as the one that came from my donor car. I may run back to the junk yard and snag that sensor as a reference.

I also think I need to get the pin out's (with voltages) for the 4 wires that connect to it and start doing some research.