i am having issues with my oil pressure guague. either that or i'm actually having an issue with the engine.

 

i have a 1987 subaru GL

and when i start the car up i get 84 lbs of pressure and occationally it'll go back down to 48. but then occationally i'll get 0 pressure, but the engine proformance will be just the same as it would normally would.. i remember my old subie giving me 0 pressure but never gave me enigine problems either.. any suggestions?

Test your pressure with an honest mechanical guage.

 

Then replace your sender - sounds like it's shorted, or the wire has partially melted through on the engine somewhere. Trace the wire and see what you can find. You may need to replace the wire back to the intermediate harness connector.

 

GD

A friend of mine describes the problem as the diaphram in the sending unit having a pinhole leak that causes it to lose pressure, thus the pressure appears to drop. I've been experiencing the same problem with my xt6. He claims the engine will shut off at around 7-9 psi, a kind of safety switch operation.

He claims the engine will shut off at around 7-9 psi, a kind of safety switch operation.

If by shutting off, you mean seize when there is 0 oil pressure, yes. There is no safety switch that will shut off your car if the oil pressure drops.

I've had several Ea82 pressure senders go bad, they start to leak oil into the electrical side and show very low pressure. If I hit the brakes at highway speed the oil would slosh up on the contacts and the pressure would drop to 0.

 

Keep in mind if the pressure were really very low the lifters would start to get pretty noisy. Like GD said, rig up a mechanical gauge to test (I layed mine under the windshield wiper for a day), or swap it with a known good sender.

 

Gary

yeah i'll try a different guague but i dont think that i'm leaking anywhere. its just that i lose pressure.. and it'll stay at 0. but then when its at 45 it stays there for a while then drops to 0. then when it is at 85 it stays there.. untill i turn off the engine.

Keep in mind if the pressure were really very low the lifters would start to get pretty noisy.

that's not necessarily true. maybe if it's sustained low pressure, but i don't think the HLA's loose pressure very quickly. i lost all of my oil and the engine seized, the valve train never made a peep. i violently ran over some firewood on the road previously and suspect the pan or oil filter were punctured causing a leak. i never verified this before having the motor scrapped though, just speculation since it was only a day or a few before the seizure occured.

 

but i was totally surprised the HLA's never gave warning when the oil pan went bone dry. but i'm not surprised after the fact because i've disassembled HLA's before and they are difficult to compress and bleed down once out of the car. they take quite a working over to get all the oil out.

yeah i'll try a different guague but i dont think that i'm leaking anywhere. its just that i lose pressure.. and it'll stay at 0. but then when its at 45 it stays there for a while then drops to 0. then when it is at 85 it stays there.. untill i turn off the engine.

 

Totally smacks of wire short - no connection = 0 psi. Grounded to the engine block = 85 psi. 45 = working correctly. I say your problem is a short either in the sender or in the wire for the manifold harness. Just a guess from having lots of experience with both stock and aftermarket guages on subarus.....

 

GD

They are not talking about an external leak but an internal leak in the sending unit. I just replaced the sender on my 87 Brat for the same problems you are describing. About $22 from Advance Auto and less than 5 minutes of my time. My would take about 15 miles to get down to 0, now it runs at 50# warm.

If your GL's Lifters are not noisy... unless you got lucky and bought a rebuilt motor like mine(which the cars still in my driveway..waiting...for tomarrow.. it broke) its doesnt have enough miles on it... also quick question subienerds... i hope you guys dont get offended by me saying that(ill be one soon enough) but.. are the lifters in EA 82s hydrolic or not?