The Top DSM Community on the Web

For 1990-1999 Mitsubishi Eclipse, Eagle Talon, Plymouth Laser, and Galant VR-4 Owners. Log in to remove most ads.

Please Support RTM Racing
Please Support STM Tuned

what is "normal" oil pressure?

This site may earn a commission from merchant
affiliate links, including eBay, Amazon, and others.

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

dsmGSTtuner

10+ Year Contributor
143
2
Mar 3, 2012
lexington, South_Carolina
Just completed a motor swap and im doing a basic check list on it. My aftermarket oil pressure gauge is reading 7 psi at cold idle. I didnt let it run too long after that because im thinking thats kinda low. Im running 10w-30. What is the normal oil pressure at idle for a 2g 4g63? :confused:
 
That is not good. When I first start my car in the morning the oil pressure is around 80. That is probably a little high, but when my car is fully warm the oil pressure is around 12 at idle, and that is perfect.

So if 12 psi when warm is proper(which it is) then you for sure have a problem somewhere. Clearance on the bearings , bad oil pump, or something along those lines.
 
dang thats a bummer...what could be the culprit? i already checked the bearings, they are fine. I did install the balance shaft delete on it...somebody else did. If that one stub shaft inst upside down do you think that would cause low oil pressure?

*i meant i DIDNT install the balance shaft delete kit...someone else did though
 
i used to sit at 30psi, 1k idle, 20W50 non synth oil, warm, and now i'm at 18-21psi but i have 5k miles on the motor and i think my bearings just broke in. oh yes and BS removed and OFH ported.

75psi cold sometimes; 60psi cold depends on the day. I never see above 90 psi at full boost though.
 
I have seen a dozen engines have crap oil pressure from a balance shaft bearing not being blocked off properly. I take the existing bearings that are in the block and just turn them so the oil passages are blocked off. If your really good you can use the oposite balance shaft to knock them out. Thats how I roll. Why have a machine shop do what you can for free.
 
I have seen a dozen engines have crap oil pressure from a balance shaft bearing not being blocked off properly. I take the existing bearings that are in the block and just turn them so the oil passages are blocked off. If your really good you can use the oposite balance shaft to knock them out. Thats how I roll. Why have a machine shop do what you can for free.

that comment isnt helpful to the topic what so ever. how about telling us your oil pressure and crap like i did so others can get an idea of what "normal" is.. there is another thread just like this and its fu$king retarted how people dont just give their oil pressure numbers.. pisses me the hell off.:ohdamn:
 
that comment isnt helpful to the topic what so ever. how about telling us your oil pressure and crap like i did so others can get an idea of what "normal" is.. there is another thread just like this and its fu$king retarted how people dont just give their oil pressure numbers.. pisses me the hell off.:ohdamn:

How is it not helpful. The op said that someone else did a balance shaft delete for him. This guy was informing him that the front bearings have to be removed and re-installed with the oil hole in a different spot. I second this, it sounds like the balance shaft elimination was not done properly.
 
How is it not helpful. The op said that someone else did a balance shaft delete for him. This guy was informing him that the front bearings have to be removed and re-installed with the oil hole in a different spot. I second this, it sounds like the balance shaft elimination was not done properly.

well he was asking what normal oil pressure is... that is the thread topic. i would think anything about his balance shafts or cause of his issue should be 2nd to what you consider "normal" oil pressure to be. only me and matt have given such info.. no one else.. answer his first question then his next one. there are too many threads with titles like this where im sure more then just myself will go to looking for an answer only to have no one giving the answer.
 
dang thats a bummer...what could be the culprit? i already checked the bearings, they are fine. I did install the balance shaft delete on it...somebody else did. If that one stub shaft inst upside down do you think that would cause low oil pressure?

*i meant i DIDNT install the balance shaft delete kit...someone else did though

Look right here, the guy asked about his balance shaft elimination. Someone was strictly answering his question. I didn't know it was not allowed to answer a question.

To answer the original question. Most of the time in these cars i see around 20-25 cold on an engine with balance shafts and 10-15 warm. On cars with the shafts eliminated usually around 30-40 cold and 20-30 warm, a little more without the filter housing ported.
 
well he was asking what normal oil pressure is... that is the thread topic. i would think anything about his balance shafts or cause of his issue should be 2nd to what you consider "normal" oil pressure to be. only me and matt have given such info.. no one else.. answer his first question then his next one. there are too many threads with titles like this where im sure more then just myself will go to looking for an answer only to have no one giving the answer.


ahem...:rolleyes: but thanks for the 2nd part of your answer :D
 
I think it's supposed to be around 11.5psi at 750rpm.

This is correct. Stock oil pressure is 11.5psi at 750RPM with the engine fully warmed up. A decent rule of thumb is 10psi for every 1K RPM. Of course having the balance shafts removed, OFH ported, head oil port mod, etc will change these numbers.

I personally have 15-20psi at 900RPM idle, about 50 while cruising depending on speed, and close to 100psi at cold starts. I have BSE, no OFH porting (yet), and no head oil port mod while running 20w50 VR1 synthetic. So naturally, my oil pressure is a bit higher than most.
 
Low oil pressure can be caused by a few things, especially when its a fresh rebuild and a shade tree mechanic assembled it.
- Low engine oil
- Oil pump
- Relief valve is stuck open
- Bearings have too much clearance​
and, if you had the balance shafts or oil squirters removed, you can tack those two possibilities up on the list too.

Before you start jumping to conclusions and tearing into things, where is your oil pressure gauge checking pressure at?

Oil pressure, as per the FSM, should be 11.4psi (or more) at curb idle speed when oil temperature is 167* to 194*. If the BS's were eliminated, assuming it was done correctly, your oil pressure should raise.

:dsm:
 
well its reading from where the oil pressure switch is located.
Where is the relief valve at? Also how could i check to see if its stuck?

The dumbass who rebuilt my engine put the wrong size bearing in it.
 
Last edited by a moderator:
that would be great! yea thanks gofer! All i really did was like it idle like that. Hopefully it didnt ruin anything.
 
My oil pressure is about 25 on cold starts....I see some people saying they have 100 does this mean my oil pump is bad?

25 on a cold start is low. 100 is for people with deleted balance shafts. On a stock car I'd expect to see 60-80 on a cold startup.

What matters more is what it maintains on a hot idle. After driving for 1-2 hours on a hot day you should still maintain 12-15psi at idle.
 
I let the car cool off,started it up and it actually goes to about 50ish psi at about 1100 rpms cold if I give it just enough gas to get to about 1300-1400 rpms it goes up to about 70-75psi in the oil pressure. my idle tends to be a little low on my cold starts because of this damn q45 throttle body. I’ve been tinkering with it to try to get it to work but all in all I think maybe the pump is ok so far anyway. I just got the car so I’m not ruling it out
 
Also I cleaned of the oil pump side of the motor have it on jack stands right now idling and am inspecting it for any leaks

also just a bit of info on the car I actually picked it up about a week ago 4 hours from my house and drove it home so you think if the pump was bad it would of already been showing some sort of engine failure maybe ticking or knocking?
 
Last edited:
Support Vendors who Support the DSM Community
Boosted Fabrication ECM Tuning ExtremePSI Fuel Injector Clinic Innovation Products Jacks Transmissions JNZ Tuning Kiggly Racing Morrison Fabrications MyMitsubishiStore.com RixRacing RockAuto RTM Racing STM Tuned

Latest posts

Build Thread Updates

Vendor Updates

Latest Classifieds

Back
Top