low oil pressure
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Cruising
Joined: Aug 2007
Posts: 10
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From: Montgomery Texas
low oil pressure
Have a friend thats looking at a 1997 to buy, he has a concern with the oil pressure gauge displaying 20 at idle. I have a 1998 with 40K miles, mine displays 40 at idle. Does this sound like a legitimate concern?
Drifting
Joined: May 2006
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From: PHOENIX, AZ Yes, it's true. You are a good woman. Then again, you may be the Antichrist.
The oil pressure sending units are notorious for going bad. But they usually peg low or high. A search will turn up plenty to read on the topic. 
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From: Horncastle Lincolnshire, England
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Ive seen as low as 25 on my 02 with a hot engine in high OATs. I only get 40 when the engines cold or when I'm underway.
I'd say its a little low but probably OK. Others with that year Vette may chime in with some of their figures.
If its reading 20 I'd say its not the sender unit. Easy to find out as the pressure will rise once you rev up.
I'd say its a little low but probably OK. Others with that year Vette may chime in with some of their figures.
If its reading 20 I'd say its not the sender unit. Easy to find out as the pressure will rise once you rev up.
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That's a very low pressure. I would want it checked out for sure.
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Tech Contributor
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From: Van Buren Arkansas
Wounded Warrior Escort '11
How many miles are on it? My '99 has 294K miles now and I see that same lower pressure. 6Psi is the minimum. I had mine checked with a mechanical oil pressure test which confirmed it. In my case, either things are loosening up in there which I expect or the oil pump is slowly wearing. I have a new oil pump ready to put in, but it appears its such a pain to get the front cover off, I haven't done it yet.
Melting Slicks
Joined: Feb 2004
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From: Loudon/Lake Mary Tennessee/Florida
How many miles are on it? My '99 has 294K miles now and I see that same lower pressure. 6Psi is the minimum. I had mine checked with a mechanical oil pressure test which confirmed it. In my case, either things are loosening up in there which I expect or the oil pump is slowly wearing. I have a new oil pump ready to put in, but it appears its such a pain to get the front cover off, I haven't done it yet.
Drifting
Joined: Oct 2002
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From: SoCal
How many miles are on it? My '99 has 294K miles now and I see that same lower pressure. 6Psi is the minimum. I had mine checked with a mechanical oil pressure test which confirmed it. In my case, either things are loosening up in there which I expect or the oil pump is slowly wearing. I have a new oil pump ready to put in, but it appears its such a pain to get the front cover off, I haven't done it yet.
Tech Contributor
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From: Van Buren Arkansas
Wounded Warrior Escort '11
I've only used Mobil 1. At this time, its got 10W in it rather than the fatory recommended 5W. I'll post pics of it when I hit the magic 300K mile mark. Looks great except...its due for paint on the front again. Those miles are freeway miles therefore it takes a toll on the front end. At this time, its looking a dull black up there. Its a Black on Black '99 Coupe. Its out here in the parking lot at work right now but no camera with me.
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If the car your friend is looking at is low mileage, I would think it is simply the oil pressure sender unit, especially since that seems to be the trend with these cars.