Low Oil Pressure Only When Hot
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Joined: Oct 2006
Posts: 92
Likes: 2
From: Austin Texas
Low Oil Pressure Only When Hot
When cold my '02 Z06 oil pressure is about 50 psi at idle. But once hot (210 oil temp) it is down to 15. I also noticed that the low oil pressure light came on occasionally during the last track session in long left hand turns even though it was filled one quart over as recommended. There is no knocking, though maybe a little more valve train sounding noise than I remember in the past. When changing the oil I found no shavings.
A bad oil pressure sensor would be best case, but most posts on the oil pressure sensor say when it goes out it just pegs high. Is this true?
I guess the oil pump could be going out, though it was replaced when the motor was pulled and new bearings were put in by a shop a couple of years ago (yeah, it gets driven hard). But if that were the case I guess I would have expected the pressure to be low all of the time at idle not just when hot.
Any insight?
Thanks!
A bad oil pressure sensor would be best case, but most posts on the oil pressure sensor say when it goes out it just pegs high. Is this true?
I guess the oil pump could be going out, though it was replaced when the motor was pulled and new bearings were put in by a shop a couple of years ago (yeah, it gets driven hard). But if that were the case I guess I would have expected the pressure to be low all of the time at idle not just when hot.
Any insight?
Thanks!
Drifting
Joined: Feb 2008
Posts: 1,596
Likes: 67
From: Bahama North Carolina
When cold my '02 Z06 oil pressure is about 50 psi at idle. But once hot (210 oil temp) it is down to 15. I also noticed that the low oil pressure light came on occasionally during the last track session in long left hand turns even though it was filled one quart over as recommended. There is no knocking, though maybe a little more valve train sounding noise than I remember in the past. When changing the oil I found no shavings.
A bad oil pressure sensor would be best case, but most posts on the oil pressure sensor say when it goes out it just pegs high. Is this true?
I guess the oil pump could be going out, though it was replaced when the motor was pulled and new bearings were put in by a shop a couple of years ago (yeah, it gets driven hard). But if that were the case I guess I would have expected the pressure to be low all of the time at idle not just when hot.
Any insight?
Thanks!
A bad oil pressure sensor would be best case, but most posts on the oil pressure sensor say when it goes out it just pegs high. Is this true?
I guess the oil pump could be going out, though it was replaced when the motor was pulled and new bearings were put in by a shop a couple of years ago (yeah, it gets driven hard). But if that were the case I guess I would have expected the pressure to be low all of the time at idle not just when hot.
Any insight?
Thanks!
Race Director
Joined: Mar 2008
Posts: 12,413
Likes: 502
From: Rio Rancho NM
Gm stated that there manual said that anything above 9psi and below 65 psi is fine. My cold pressure is 70-80 cruising and wot warm is 50's. Hot idle at 230 is about 15. I'm boosted and have 100k on the car. This is with a new pump..You can always check with a mechanical gauge but sounds like you are withing operating temps. I'm sure the sky is falling folk will come in but again that's within operating values. As long as it goes up during cruisng and wot you have nothing to worry about. IMO
