RedL98

I've noticed my oil pressure has gradually dropped. When the car is cold and idling the pressure on the gauge is about 1/3 from the bottom. When it warms up and idling it shows no pressure. When I accelerate when its warm it goes up to about 1/3 on the gauge. I checked my oil level and it full. What could be the problem? I did go to a shop they checked it and said it was fine its probably just the gauge. Is this probably it or is it something else? Thanks.

Apeiron

If you don't trust the shop, check it yourself with a mechanical oil pressure gauge.

RedL98

Thanks. What are the steps to check it?

joe350

I've had the exact same problem for about the past nine months. No drivability issues though.

Air_Adam

- Buy mechanical guage
- Hook up guage to motor... there are spots around the oil filter boss and right under the distributor.
- Start engine and watch guage.

86TpiTransAm

I would say that if your guage is running that low and even at 0 sometimes and the engine hasn't locked up yet, it's probably the guage or sending unit. I would replace the sending unit first. I had the same problem on my Beretta GTZ and replaced the sending unit and it fixed the problem. Should be fairly cheap replacement part.

sqzbox

Had a problem with my 305, dropped to 0 psi and bought a mech. gauge and it showed 40 psi. Old electric gauges wear out and lie!

taonindo

mechanical is best imho but i run both in my car 1 at dist. and elic. at the oil filter... they hardly ever agree with each other ...at start up the elic. will show 45psi and the mech. one will show 60psi...........tao

m390

i have never seen my gauge get above 40psi i think the gauge or sending until is bad on mine but again when im at a red light my car idles at like 500rpm dunno why bit it does and my oil pressure gauge read 0psi when im idle

sqzbox

Yup, my chevy truck (75) has a direct mech. gauge that is fed from the port beside the dist. and reads 60 psi. It's a factory mech. gauge that is 30 yrs. old. I installed an after mkt. gauge from the front port behind the water pump and it reads 40 psi at 3000 rpm. I figure that the fact. gauge is worn and reading high OR, my bearings are really worn and I'm losing pressure between the pump and the front oil passage. Only way to find out is install another after mkt. gauge from the port where the fac. gauge is hooked to. Mech. gauges over a long period of time loose tension in the spring that governs the needle reading and show a higher psi than what it actually is. Electrical sending units for some reason, tend to read lower.