LarryD

What is the correct oil pressure sensor.??. This is an all stock from the factory original 3.1L with Oil Pressure gauge.. My current one is leaking and of course the auto parts place gave me totally the wrong one.. Way to big in diameter to screw into the fitting... Mine is shorter and the threads are small diameter.. It is a three wire connector... Anyway, does anybody have some correct part numbers and is the correct one suppose to shutoff the fuel pump when there is no oil pressure? The last one didn't... Also, I have had trouble with them reading either way to low or pegging the gauge in the past....

Thanks...

LarryD

Ok, so gave up and bought another one.. This one was a bit longer but had the right thread base.. After market lists it for a 91 3.1L only.. However, crossing the AC Delco number for a 92 shows the same part as for the 91...

Now, I am back to the old problem of the gauge reading just above the low mark (about 1/4) all the time... The last one read about 3/4... The first one years ago was High all the time... If I disconnect the plug from the sensor, the gauge reads about 3/4 and the car continues to run (doesn't kill the fuel pump)... So, that is strange...

At least right now I don't have the oil leak any more...... But, this whole gauge/sensor combination doesn't seem to be working right....

ItstillaV6

92 Camaro RS's, with a stock, factory installed 3.1L, use a guage on the dash. When purchasing the sending unit, you have to order the option with the "Light". It is a smaller sensor, than the "Gauge" style.

All 92 RS's, with 3.1L engines, have the gauge with a red area near the "L", and a yellow area about 3/4 of the distance with 3 lines, or the "Normal" operating range.

I made the same mistake, when i ordered the sending unit for my 92. I told the guy I had a gauge, and he had to price me for a 91 RS sending unit.

If your sending unit is only reading 1/4 or the way, then I get a "manual" oil pressure gauge. I'm talking old school here. The style that will thread into your spot on the engine, and I would attach it to an oil pressure gauge. You should have close to 70 psi of pressure, normally. That will tell you if the oil pump is operating properly, or not.

The sender may be reading the proper pressure, for the calibration of the sender. "Light" style senders have a different spring, than the "gauge" style senders. The "gauge" style senders are used for camaros, with a gauge that reads 0-80psi.

My Camaro doesn't have the extra oil pressure sensor, that shuts off the fuel pump. So it may be possible that the engine was changed, as roughly 10% of all LH0 3.1L had crank failure problems.

LarryD

Update: So, I took back the sender units and started over.. I used an old school gauge directly connected to the base of the oil filter (in place of the sender).. My oil pressure at idle is 30psi and 60psi at high rev.. Using a new sender unit for a gauge gives me about 1/4 on the instrument panel gauge (just above red) and using a new sender unit for a light gives me about 3/4 on the instrument gauge just below the first yellow mark..

Now for the "I am not sure I trust it" category. If I leave the sender unplugged, the instrument gauge sits about the same spot as when the sender for the light is plugged in. Revving the engine doesn't seem to change the position of the instrument gauge when plugged into either sender unit type.. Makes me wonder if the instrument gauge acts as a go/no go gauge only...

Using an ohm meter on the sender pins, I get all open circuits no matter what pair of pins I use except on the center pin checked to the case ground. The center pin to case reads only about 7 ohms... The wiring diagram on a 92 says that one set of pins is a switch to ground and that the other set is a variable resistor (with pressure) of about 68 ohms.. That does not seem to be the case...

It appears to me that all of this is just a switch with the gauge showing zero if there is no pressure and the gauge showing 3/4 if there is pressure.. But, the really scary part is that no connection looks like oil pressure...

So, anybody have a clue..??.. I am puzzled.... Any GM parts or service guys here that know what's up???

ItstillaV6

Mine does the same thing, when I unplug it. If I unplug the sender, it reads all the way up to the last line, of the yellow. Maverick knows the specs on how much oil pressure you should have. I think around 70 psi, high idle, cold start is normal. So your oil pomp has definitely seen better days. In any case, your pressure isn't low enough to be too worried about, unless of course you are drag racing it, or driving really hard all the time.

I would say, to try calling a GM dealership. I would also like to say, that the owners here on thridgen are more knowledgeable, than GM service techs. The service guys, in my area couldn't tell me anything about the vapor vent valve, on my fuel tank, other than it was discontinued. Autozone showed a part, for a Blazer fuel tank, and it mounts in the tank, not on the pump. They swore that was the part I needed though. So, unless you can find something here, or elsewhere on the internet, you may have some trouble finding the information you need.