"Low" oil pressure question...
Thread Starter
Drifting
Joined: Mar 2011
Posts: 1,807
Likes: 331
From: Ocala FL
"Low" oil pressure question...
I did some research and have seen plenty of threads about high oil pressure usually being a bad sensor. Well, does it work the other way too? Have the bad sensors been known to show "low" oil pressure? The reason I'm asking is because lately I've noticed that when I start mine cold she idles at 30-32 psi. When driving increases up to around 40-42 psi (4,000 rpm and above). But when idling and around 1200-1500 rpms once warm and up to temp it's been hovering around 19-22 psi. Granted it's been in the high 80s and low 90s but that just seems low to me. Car has 102k miles and I'm running 5w30 mobile one. Does this sound fairly normal? Am I worrying about nothing? Thanks for any insight.
Tech Contributor
Joined: Dec 2006
Posts: 10,962
Likes: 29
From: Van Buren Arkansas
Wounded Warrior Escort '11
That sounds very normal too me. Will give you some respective info on my super high mileage '99..the other day I was stuck on the freeway out here due to a truck fire. My oil pressure was hovering around 10-12 psi. Yes, I know all too well its getting to be time to rebuid the lower end and put in a new pump. I have the new pump already and a new timing chain/gears and have to start acquiring bearings and so on.
Minimum to run is 6 psi
Minimum to run is 6 psi
Drifting
Joined: Apr 2009
Posts: 1,898
Likes: 9
From: Morrisville PA
The question is not the raw value of your oil pressure...it is the change...
Has it always idled at 21 psi when warm? Or did it drop like 10 psi or so? Because if you did notice a drop, then yes, you may have a problem.
Has it always idled at 21 psi when warm? Or did it drop like 10 psi or so? Because if you did notice a drop, then yes, you may have a problem.
Racer
Joined: Aug 2001
Posts: 310
Likes: 0
From: Tomball Texas
^^ Agree..
Mine only has 58k on the clock and has always had what I consider "low" oil pressure.. Mine will show 45-50psi cold start and then ventrure down around 23psi at 210. However, the oil pressure increases and decreases with RPM at operating temp.
Mine only has 58k on the clock and has always had what I consider "low" oil pressure.. Mine will show 45-50psi cold start and then ventrure down around 23psi at 210. However, the oil pressure increases and decreases with RPM at operating temp.
Melting Slicks
Joined: Jan 2009
Posts: 2,127
Likes: 33
From: Easley/Anderson South Carolina
Could also be the oil you are running and the temps outside. I notice a large diffence in my 3500 ram between cold and warm weather idle oil psi's (really havent driven my vette enough to get an accurate opinion with it.)
Advanced
Joined: Apr 2007
Posts: 69
Likes: 0
From: SHREVEPORT LOUISIANA
1999 hardtop with 61000miles, engine light comes on after warmed up and noticed 12-18 psi oil pressure at idle then 28 to 33 psi when reved up. what could be the problem? do i need an oil pump? how to check sensor etc...
Advanced
Joined: Apr 2007
Posts: 69
Likes: 0
From: SHREVEPORT LOUISIANA
had no problem until added headers and stage 2 procharger upgrade, now runs great but engine light comes on with oil pressure low after warms up 10 to 16 psi at idle and 33 to 38 on reving engine. could it be oil pumm with only 61000 miles on the car? could it be sensor? HELP?
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
Burning Brakes
Joined: May 2005
Posts: 797
Likes: 10
From: Upper West Side, NY Very Downtown Houston, TX
After my recent rebuild I have made the following chart. If I notice a sudden deviation from this chart I know I have a problem. I am using mobil 1 15w50, mobil 1 filter, and have an oil cooler.
Here are my numbers:
RPM x 1K (Column 1) TEMP (column 2) PSI (column 3)
1 93 49
1 135 43
1 147 42
1 150 41
1 160 39
1 170 37
1 175 37
1 180 36
1 190 34
1 194 36
1 200 33
1 210 31
1 212 30
1 216 32
1 217 31
1 219 29
1 223 29
1 225 28
1 230 26
1 232 26
1 240 23
1 241 26
1 252 22
1 253 19
1 255 19
1 257 20
1 259 19
1 262 19
1 264 19
2 93 57
2 135 50
2 150 46
2 175 42
2 180 41
2 190 40
2 200 39
2 210 36
2 217 35
2 225 33
2 223 33
2 230 32
2 232 31
2 240 28
2 241 30
2 243 32
2 253 29
2 255 26
2 262 26
3 93 66
3 135 69
3 150 53
3 180 48
3 190 46
3 200 44
3 210 43
3 217 40
3 225 38
3 230 35
3 232 35
3 240 32
3 248 35
3 255 30
3 262 29
4 93 71
4 135 65
4 150 57
4 180 51
4 190 51
4 200 48
4 210 46
4 217 43
4 225 40
4 230 39
4 232 39
4 240 35
4 246 39
4 255 32
4 262 30
5 275 31
Instructor
Joined: Sep 2010
Posts: 117
Likes: 0
From: Michigan
had no problem until added headers and stage 2 procharger upgrade, now runs great but engine light comes on with oil pressure low after warms up 10 to 16 psi at idle and 33 to 38 on reving engine. could it be oil pumm with only 61000 miles on the car? could it be sensor? HELP?
Does the procharger use engine oil? If so it may use enough oil volumn to lower the total oil pressure...maybe.
5th Gear
Joined: Dec 2015
Posts: 5
Likes: 0
Low psi
I can't say what is normal for 102K miles but my 04 with 28K idles at 40 to 43 in our current 100+ temps in traffic. I personally would not be comfortable with 20 or under at idle but that may just be me.
As far as the pressure sensor failing and reporting low pressure, there have been a few posts reporting that. But the majority report high readings at failure. Also a common indication of pending pressure sensor failure is guages reporting pressure readings with the engine off key on.......
As far as the pressure sensor failing and reporting low pressure, there have been a few posts reporting that. But the majority report high readings at failure. Also a common indication of pending pressure sensor failure is guages reporting pressure readings with the engine off key on.......
I just changed out the pressure which, got finished putting everything back together started my 00 C5 witb 66k and now I'm getting low PSI its reading 0 what could this be from?
Drifting
Joined: Feb 2008
Posts: 1,596
Likes: 67
From: Bahama North Carolina
Advanced
Joined: May 2015
Posts: 70
Likes: 3
From: CA
That sounds very normal too me. Will give you some respective info on my super high mileage '99..the other day I was stuck on the freeway out here due to a truck fire. My oil pressure was hovering around 10-12 psi. Yes, I know all too well its getting to be time to rebuid the lower end and put in a new pump. I have the new pump already and a new timing chain/gears and have to start acquiring bearings and so on.
Minimum to run is 6 psi
Minimum to run is 6 psi
. Mine went to 8 last year (look at current post of mine ....) I pulled the motor had two spun cam bearings motor only had 3k miles on it due to QMP handy work. I did some research and have seen plenty of threads about high oil pressure usually being a bad sensor. Well, does it work the other way too? Have the bad sensors been known to show "low" oil pressure? The reason I'm asking is because lately I've noticed that when I start mine cold she idles at 30-32 psi. When driving increases up to around 40-42 psi (4,000 rpm and above). But when idling and around 1200-1500 rpms once warm and up to temp it's been hovering around 19-22 psi. Granted it's been in the high 80s and low 90s but that just seems low to me. Car has 102k miles and I'm running 5w30 mobile one. Does this sound fairly normal? Am I worrying about nothing? Thanks for any insight.
Racer
Joined: Apr 2013
Posts: 333
Likes: 10
From: Gilbert AZ
I'm currently going down this road and I am waiting for my scheduled appointment with a race shop/engine builder.
Could be a few different items ...
1. Oil pump
2. Oil pump Gasket - O ring
3. Bearing clearance
From what I have been told - The Best thing to do is put a mechanical pressure gauge on it and see where its at and go from there.
Could be a few different items ...
1. Oil pump
2. Oil pump Gasket - O ring
3. Bearing clearance
From what I have been told - The Best thing to do is put a mechanical pressure gauge on it and see where its at and go from there.
