Hello All,
I have an '89 Iroc-Z with a 5.7 TPI. The oil gauge is no longer working and it looks as though it needs an exorcism! It shows about 180 PSI at idle.
I bought and replaced the oil pressure switch above the oil filter with an AC/Delco unit but it didn't make any difference. Normally it would peg high when I started the car but would come back down and read normal. Now it just does what you see in the picture, regardless if the vehicle is on or not. I was doing some research on thirdgen.org and came across a thread that noted that some Camaros had the oil pressure switch up top by the distributor. When I checked the GM service manual it said nothing about that switch being up top, just by where the filter is. Were there two separate oil pressure switches...one for the ECM and one for the gauge? I'm beginning to think that it has more to do with the gauge itself or the printed circuit. Does anyone have any experience with this? Is there a service to restore original equipment?

Thanks

 

Does anyone know of a service that rebuilds these stock gauges? I can only seem to find used tach/oil pressure gauge for sale. In fact, I haven't found any new...other than aftermarket. Lots of choices with 2nd gen, not so much with 3rd gen.

 

Mine used to be pegged all the time too, it was the oil pressure sending unit located near the distributor, looks like a brass bell. Managed to R&R without removing anything as long as you have some extensions and are careful. Check Rockauto I replaced mine with a AC Delco that worked good.

On my 88’ L98 there are 2 oil pressure sensors, one near the oil filter and the one near the distributor that runs the gauge. My understanding is the oil pressure sensors change throughout the years.

 

Yeah they moved the switch around, doesn't really matter from a functional standpoint which place it's in, just gotta make sure the other one is plugged and the wires reach it. Most of the later cars with the 3-wire sending unit for EFI have it by the filter but I don't think anywhere near all of them do.

You can ground the tan wire at the sending unit with the key on, and the gauge should go to 0.

You may well find that if the gauge is merely pointing around backwards like that because it got past the end stops somehow, you can just take off the bezel, move it past the stop to 0 with your finger, and it might work just fine after that.

 

Thank you, gentlemen. I'll look in to that and report back.