Oil Pressure Falls at Idle

Low fluid level in the trans makes it harder for the internal pump to keep drawing fluid from the transmission pan. If you accelerate and the fluid is low, it drains away from the pump pickup and the pump sucks air. Air can’t be used to shift gears, it takes oil. If it is losing trans fluid, by all means, check it very regularly and add as needed.

Thanks Old timer, no I’m checking it regularly and topping off as needed, I will say it appears to need 1/2 quart over the “full-line” hashmarks to make it run without the psi dropping to 5-6 psi at idle

I hope everything turns out OK for you. Good Luck and we’ll give you as much help as we can.

I’d call this a radiator per se:
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Did your ac work properly? I had a new compressor put in and it only blows cool on the drivers side, ice cold on the passengers…and please don’t say :“blend door” as I sure can’t pull the entire dash. When I top it off with a can of Freon (so expensive) it works great for a week…It was 113 here last week and my little boy rides home from school in my beast. thanks

Oh, and I had to pull the driver side door panel to replace the door handle a while ago, maybe I loosened a wire so the drivers electric seat won’t move?

Should I have the mechanic I paid to install the intake manifold take a look for leaks? He took quite a long while to do the install for me…I got the impression he had trouble with it.

So helpful, thanks. I can tell you I have no “symptoms” resulting from these oil pressure readings, no knocking, no bogging down, it runs like a race car (and the Northstar engine is a beast), so your theory holds water. If it was more “serious”, I would expect to notice issues with the way the car runs, some sign that things weren’t right, I have no valve tap, no hesitation off the line, it sounds like a top.

and thank you Cavell for your valuable time.

I misunderstood the explanation, it is only “integrated” but I appreciate your pointing out my error.

Thanks M-Man, I’m so thankful for the help…I couldn’t have figured most of this on my own.

the northstar 4.0 and 4.6 are known for leaking headgaskets due to headbolts pulling.
using coolant? there you go.
have you replaced the oil pressure sender? cheap part

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Just a quick note then gotta go. Of course check the fuses. There are a couple fuse blocks under the back seat where I believe the breaker is for the seat. The motors have an internal breaker that will not reset until voltage is disconnected. So maybe try that first by pulling and inspecting the breaker.

Maybe there’s nothing wrong at all with the oil pressure. I just looked it up and for the normal oil pressure , the manufacture’s specification for the 1996 Oldsmobile Aurora 4.0 is 5 psi at idle, and 35 psi at 2000 rpm. What does your gauge say the oil pressure is at 2000 rpm?

I would think you need a little more than 4-5psi at idle to keep the low oil pressure warning from lighting up

The source is All Data. Maybe somebody else can look it up to confirm/deny.

I will do that this week, thanks. It’s definitely leaking at the head gaskets…and the pressure has improved since our heatwave snapped, we went from 112 degrees to 82 in a week.

It goes off as soon as it drops to 6 or lower…

Sorry, now I understand…this would make more sense since I am seeing no signs of the car running poorly at all. It doesn’t run rough, no valve taps or clatter sounds when I accelerate, no reason to believe the warning is relevant. I’m pretty sure there is some electrical issue going on, just hoping it’s not like the ECM (the “brain”) since so many electrical parts are failing.
My drivers side power seat won’t move, neither rear view mirrors move, my cruise control is out (and this happened over time, it was intermittent then stopped, gas gauge is all over the place…

How to test a breaker? Thanks