Hello, I have a 1985 3.2L engine. My oil pressure warning light kept lighting on and off but my pressure gauge was jumping all around. I had diagnosed this as the oil pressure sending unit going bad. Today I replaced the sending unit and the oil light stayed off then after a short while of running idle came on again. The gauge seems to be accurate after the replacement and reading correct pressures however the light has remained on after my sensor change.

Has anybody run across this or have any advice? My main concern is whether or not the car should be driven as I’m thinking there is correct oil pressure but do not want to do any harm.

 

Your oil pressure gauge and warning light were both acting wonky, you replaced the oil sender, and at maybe the gauge is reading OK, but the oil light is still not right? And you are "thinking there is correct oil pressure"? I assume you haven't seen a massive oil leak anywhere, but personally, I would not run that engine until the problem was definitively diagnosed and fixed.

 

Yes my oil light would intermittently come on and off seemingly random times despite not having major oil leaks. The Gauge reading the pressure would peak and fall but occasionally work. There are no major oil leaks I looked around. I reinstalled the original sender cleaning the contacts and it seems to have fixed my pressure reading but my oil light remains on. I found out about the oil pressure switch towards the back which I am now thinking may be my problem. I removed the air box and cleaned the connectors but it did not solve the light either. Thinking I’m going to end up ordering and fitting a new one and seeing if that resolves it unless I can somehow test the one that’s in there currently. Otherwise the car has been running fine no changes to sounds I hear or anything just that light wanting to stay on.

 

they are completely independent sensors.... if both your oil light and your oil gauge are telling you something is wrong, i would not " kill the messenger" and just change the parts that are telling you something is wrong.

 

time to put a known working manual gauge on the car to validate under starting condition (ie not running).

There are off the car electrical checks you can do of the components.

If your car is 'reasonably' well worn it's possible the oil pressure light can come on at idle when the car is hot. That light should NEVER come on above 2k or so RPM.

 

Coming back to this forum after solving the problem. I ended up ordering a new pressure switch and adapter as well as a sending unit and this has resolved all issues I was experiencing. I purchased an independent oil pressure gauge and will verify the readings are correct, but seems it was just a bad switch. Thanks for your help and suggestions!

 

that doesnt make sense as the pressure light and gauge come from completely different sensors on separate ends of the engine.

 

Im not quite sure what you mean could you elaborate more? I pulled the air intake out and was able to get to the back of the engine and replace the switch for the light on the dash. As well as installing a brand new sending unit towards the front of the engine. Am I missing something or are those the 2 separate sensors?

 

yes they are ... it has to be the most amazing coincidence in the world that both your independent sensors would go bad at the same time and indicate oil pressure issues.

the one under the intake close to the firewall is the low pressure light, and the barrel one close to the back of the car is the gauge.

im very happy for you though , as this is the best possible scenario when it comes to engine oil pressure.