Low Oil-Pressure issues...

[Nt-Eclipse-Dail]

I was hoping you guys could help me figure out a Low Oil-Pressure problem that I have been dealing with lately.

The car is a 1991 Mitsubishi Eclipse NT 1.8l with @236,000k on the clock.
Engine has a fully reconditioned top half (fresh cyl. head) and is well maintained and keep in good running order. This car is my daily ride, So I try to be real nice to it.

When I was doing the top of the engine at 230,000k I noticed VERY little wear on the cylinder walls. There was 'barely' even a ring-ridge at the top, and the pistons were 'extremely clean', so I did not touch anything on the bottom-end of the engine other than to replace a waterpump and timing belts while I was in there... The engine had what I call 'normal' oil-pressure before the head-job but now after about 3 to 5k miles later, the oil-pressure seems to be steadily dropping. I got nervous when it started to dip below the low-pressure 'tic-mark' on the guage after idiling for a while, but now it sees to be below the tic all the time unless I am cruising at interstate speeds...

I did replace the oil-sending unit when I first noticed the problem and there was a 'slight' change for the better but the pressure is still way too low for me...
I do believe that my rings may be bad because the car spits a very little bit of stuff out the exhaust when idling for a few min. (but the clyinders looked REAL good for the miles they had...

Do you think I need new rings and bearings here, or is someting else going on?
Can anyone point me to some oil-pressure related posts?
Are the bearings a PITA to replace on these engines, and can it be done with the engine 'in-the-car'??? Any advice on the bearings and\or their replacement would be greatly appreciated...
Has anyone continued to drive their car like this for a while, or am I just waiting for something to go out on me?

I appreciate the help and I appreciate your DSM forum guys...
Thanks for reading!

 

[1.8laser90]

idk what low pressure is but mine seems low too i have also done top end rebiuld with new cylinder head about a month ago... i think this is normal but if u have a camera and take a pic of it when its low but i wouldn't worry about it that much cause there all like that when old its just the bearings there worn and it just looses oil pressure its still getting the oil it needs but just not alot pressure. just make sure theres oil in it and u should be fine

 

[Erix]

mine has been the same way but i only have 72k on mine i guess my exhaust is to close to my oil pan though and its getting to hot i did a oil change and its pretty good now but it still dips sometimes i think it just might have something to do with 1.8l engines

 

[Crazy E]

This is the exact problem I have with my car, and its been doing it for a long time now.

I wish someone had a more concrete answer as to why 1.8s seems to do this and if its something to be worried about.

 

[Erix]

yea i know whatcha ya mean i wish someone would invest into some 1.8 info it would help a lot of people out. worrys me cuz im afraid of going to somewhere then my engine just dies...that'd be no good

 

[nisreo]

Ive got really low oil pressure on my 2.0. To the point my oil light comes on when idling. It goes away as soon as I hit the gass.

 

[1.8laser90]

this might give u an idea of proper oil pressure click here

 

[Crazy E]

Thanks for the link!

I believe that my oil psi is low as result of a leak, which I think is my oil pan gasket. The headgasket I recently changed is also still leaking slightly (see post in problem diagnosis)

Anyway, is this oil pan gasket an easy job? Would it result in higher oil psi?? Is it imperative that I tackle this job now (at school, working on cars in the lot sucks)

Thanks!!

 

[Defiant]

Thanks for the link!

I believe that my oil psi is low as result of a leak, which I think is my oil pan gasket. The headgasket I recently changed is also still leaking slightly (see post in problem diagnosis)

Anyway, is this oil pan gasket an easy job? Would it result in higher oil psi?? Is it imperative that I tackle this job now (at school, working on cars in the lot sucks)

Thanks!!

Your oil pan gasket has nothing to do with oil pressure.

 

[Crazy E]

damnit Defiant, why you always gotta make me look like a dummy!!!

, at least I know thats not the problem with the oil psi then


but.......what is the problem then??

 

[hkdl]

My 2.0 has the same problem, I've just been ignoring it .

 

[2-0turbo]

The other key is you need real numbers. Get a real pressure gauge and see what you are running. If it is low and you have replaced the top end, I would suggest, as others have, that your lower end bearings are worn. Oil pump failures are uncommon, but the clearances are probably pretty loose and it might not be functioning 100% after 236K miles. If your oil pressure numbers indicate lower oil pressure, you can increase the viscosity of your oil a bit to compensate.

Bottom line, if you have had 236K miles without going into the motor, consider youself lucky. They don't last forever.

 

[Crazy E]

I currently using 10w-30......should I start using 5w-30?

I dont get oil numbers

 

[1.8laser90]

no ud wanna go up maybe 10w- 40, 15w-40 some people even try 20w-50 which i think is to much but... the thinker the oil the more pressure ull get but u don't wanna go crazy and get the thickest oil so your pressure will go sky high, thats not what u want. test with diferent types of oils and W of oils, every engine is diferent... I use 10w-30 and don't have a prob but i also don't have alot of miles on mine..

 

[Defiant]

I dont get oil numbers

http://www.micapeak.com/info/oiled.html

 

[JustInsane]

Bottom line, if you have had 236K miles without going into the motor, consider youself lucky. They don't last forever.

well i must be really lucky i have 273,500 miles on it.. i have a bad oil pressure too but i got the car for free so it doesnt really matter what i do to it.

 

[na90dsm]

http://www.dsmtuners.com/forums/showthread.php?t=145227


thread on getitn higher oil pressure. a few little tweaks you can do.

 

[Nt-Eclipse-Dail]

Can any of you guys educate me about oil-pump replacement on these cars?
Do I have to remove the engine, or can this be done with the engine in the car?

I found a high volume oil pump for the car, I was just looking for some tips on the installation...

I appreciate all of the input from you guys, Thanks...

 

[realitytb]

i dont know if this helps, but below 3,000 RPM your oil pressure should be BELOW the "L" tick mark, and very slightly above it at 3,000 RPM. My oil pressure goes almost down to the end of the gauge when i idle. and every thing is perfectly fine. ive had it checked out, by myself, and other mechanics, and its perfectly fine. im going to replace my sending unit to see if that does anything, but i wouldnt worry about it too much unless the oil pressure light comes on. then you stop your car.

 

[Nt-Eclipse-Dail]

i dont know if this helps, but below 3,000 RPM your oil pressure should be BELOW the "L" tick mark, and very slightly above it at 3,000 RPM. My oil pressure goes almost down to the end of the gauge when i idle. and every thing is perfectly fine. ive had it checked out, by myself, and other mechanics, and its perfectly fine. im going to replace my sending unit to see if that does anything, but i wouldnt worry about it too much unless the oil pressure light comes on. then you stop your car.

That is just NOT true...

I have been driving this car for a few hundred thousand miles now, and I know.
The 'L' on the oil pressure guage stands for 'LOW'. I understand that the book says it is O.K. for the needle to drop below the 'L' sometimes when at idle, But Just because they say it's O.K. does not mean that is where it is supposed to be all the time...
Up until my car hit 200,000 miles +, the oil pressure NEVER fell below the 'L' (not even at idle). I am looking to repair or replace whatever I need to to get things back straight again... If anyone has any info on rebuilding our type of engine, please post up...

 

[1.8laser90]

there is a faq on dsmtalk about 1.8 rebiuld posted by ginsu417 but dsmtalk is down right now and can't get to it

 

[cornfed]

I did a web search for low oil pressure because I have the same problem. The results suggest checking the sender and type of oil for starters but then gets really indepth about oil pressure systems. To get to the point, have your bearings checked. See what the gap is on them. That seems to be the culprit for the majority of the advanced problems. If the gaps check ok, then your oil pump is probably going soon. That's just what I've found to be the consensus. Good luck.

 

[Crazy E]

no ud wanna go up maybe 10w- 40, 15w-40 some people even try 20w-50 which i think is to much but... the thinker the oil the more pressure ull get but u don't wanna go crazy and get the thickest oil so your pressure will go sky high, thats not what u want. test with diferent types of oils and W of oils, every engine is diferent... I use 10w-30 and don't have a prob but i also don't have alot of miles on mine..

i think i might try 10w-40 (once I get a paycheck)

is anyone else using this? has your oil psi gone up?

 

[cornfed]

I've been running 10W-30 with no luck on the oil pressure coming up. Taking it to the dealer to see if they have a better idea than me.

 

[Crazy E]

I changed to 10w-40 today and I am impressed with the results so far

the oil psi seems to be higher before it reaches operating temp and even after driving like 20 minutes in stop and go traffic the oil psi would not dip below the "low" mark on the gauge. It would still drop at idle (which is normal), but while driving it stayed right where it should be


I would suggest that any DSMer that is having problems with oil psi give it a try, it seems to have worked for me so far.


note: I used Castrol GTX high mileage 10w-40, castrol is my personal favorite

thanks everyone (especially Defiant and 1.8laser90)