Nosferatu

Just noticed this after having the car sit all night. Car drove fine but oil pressure shot sky high. After 15 minutes of normal driving it gradually started to come back down to normal.

Thoughts?

Cause for concern?

This happened once remotely in the past and I just blew it off. Now it happened again.

ajrothm

Either your oil pressure sending unit is glitching out or has a bad ground signal... Or your oil pump bypass or something is sticking.. I'd change the oil and filter first to make sure it's not filter related also.

I just had my 2 year old oil pressure sending unit fail with only 8k miles on it and it would start at 80 psi and then peg out at 130 psi after a few seconds with the key..engine off. New sensor at the Chevy dealer was $95 ��

7SECONDS

I had a similar problem in the past with an Old School Small Block Chevrolet. It was caused by a faulty check valve in a Fram oil filter. It caused major oil pressure issues. I changed the Oil filter and oil pressure went back to normal. Since then I only use K&N Oil Filters. It may not be agood idea to keep driving it because you may have 70 psi at the sender for the gauge and 0 psi at the cam bearings. Check with Matt before you go any further.

sick cc

oil pressure sensor located at the back of the block, behind the intake manifold. had mine do the same thing.

7SECONDS

I am pretty sure it is fixed now but do not know what happened.

Nosferatu

meaning???

Never figured it out but so far it's stopped doing it.

DOUG @ ECS

It's typically the sending unit, as others already pointed out.

schpenxel

Pretty easy to swap out the sending unit to be sure. I don't think I've had a LS based vehicle make it to 100K on the original sending unit yet. They fail like crazy

It's right behind the intake manifold. It can be swapped without removing the intake, but it's a lot easier with the intake off.

(ignore the banjo fitting that's in this picture.. that won't be there normally)

Nosferatu

Last I checked when a car is OFF the oil pressure should be ZERO. Well the car started up and showed 78psi. I turned the car off and recycled ignition without starting. Car read 33psi.

78 - 33 = 45psi on cold start idle. Yup normal. I think I'm good now. It intermittently likes to read weird I suppose.

JetstreamGS

Wet sump I'm assuming? My dry sump pegs the gauge on cold start.

Nosferatu

Correct it's not a grand sport