soo...seeing low oil pressure lately

only happens after its been running for a little while and all is up to running temp. When starting up it reads about 60-70psi to the head at idle. after warm up it reads about 20-25psi while running and about 3-5 while at idle (again..do the head). Just did an oil change last fri...dont rem it doing this before that but i wasnt driving more then 3 miles at a time so it may have been. Im running 5w-30 royal purple like i have been and using a k&n oil filter.

no leaks that i can find and no oil on the driveway after sitting. no blue smoke from what i can tell, but i need to have it reved up during the day when i can look from outside the car. still pulls hard and no new noises.



anyone have input?

 

time for a compression test :p

 

yup, gonna do one, that will apply if it is piston rings (will fix with wet compression test) or head gasket.

other thing i need to check is to see if i have TOO much oil, i was reading that if i have too much that the crank spinning can whip it up and make bubles, causing it to airate (sp?) and as it goes through the pump and thins back out it puts air in the oil lines and cancause low pressure. Other thing is maybe the oil filter is fubar

TTT...need more opinions

ok, so did some more looking into it today. Made sure everyting was tightened down. Pulled the filter and all looked good, re lubed the o ring and reinstalled.
removed some oil, looked fine, replaced the removed oil with some new.
no leaks elsewhere
went driving for a while, got everyting to temp and it got down to about 8-10psi at idle

thing that worries me now is that it smells slightly like a 2 stroke...not much, but a lil.

no blue smoke that i could see, a lil black but i know im running a tad rich. running catless so its hard to smell whats all in there


help me out here!!!!

didnt do a compression test as i was too lazy today haha, but everyting seems to run just fine, pulls hard still.

dont have the setup right now to do a leak down, but will do maybe next weekend if i have the time.

BUMP BUMP, help me out here

 

Bump for some help!!

 

ahahaha u blew the head gasket niceee job , buy the high performance racing gasket good for life the one they put on are crap , its a gm thing it goes on all car made by them

 

but if it was the gasket there would be oil in the coolant and vs versa...

 

its not a gm thing at all. do you know what your talking about? ive heard of way more problems with aftermarket head gaskets then with the stock head gaskets on these cars as well.

 

8-10 sounds a little low, but your gonna have to find the specs. On our cars at work, operating temps its around 14 psi at idle. When it drops below 12 or 13 then our **** flags vvt codes, cold start up i've seen 60 or so psi. It could be normal to be that low i've never seen specs on it.

 

im running on a stock one with only about 5k on it

 

That's low. Maybe the oil pump is going? Just a thought. Something might be getting ready to let loose.

 

from what ive read it should be 10-17 at idle and its running 4-8 after warm up...

 

4psi is the minimum at idle, anything over 30 is okay at 2500 RPM

 

ya, if anything i think its the valve seals as the ones i have in there were in the head off the car for who knows how long (bought from another member) so they could have dried out a bit, or it piston rings as i run the car pretty hard...

either way id pull and redo both

if it is the pump thats pulling alot to replace too if i remember right...

not hitting 30 i dont believe, but is that psi at the head or block?

 

at the oil pressure sending unit(im not sure where that is on this car, probably by the filter.)

 

ok, so the stock one is on the block, so that means minimum is 2 psi at idle and 15 under load on the head...cause all are half on the head..

 

FYI, my pressure is approximatley 20-25psi once it has warmed and stabilized. My sending unit is on the drivers side of the head.

 

ok, how warmed up...cause mine is like that for a little while, then as the oil gets warmer and warmer (even after coolant is up) then it gets lower.

and is that at idle or driving?

 

I'm speaking fully warmed, after the coolant is up, and after driving for ~10 - 15 minutes. After I reach that point, the pressure doesn't change much from idle to full throttle, maybe 5 psi max.

The pressure will do that. On a cold start, you should get approximatly 60-70 psi, until it lowers and stabilizes at operating pressure.

 

ya, mine gets REALLY low at operating temp and goes up to the low 40s under wot high rpm conditions..

 

Oil Pump?

 

i have noticed mine is dropping lower after sitting in idle for a period of time. I wasn't sure though if mine is my aftermarket oil pressure gauge sending unit or if its the actual oil pump. It is kind of hard to believe though that the oil pump would be getting ready to fail already. I am almost thinking mine is my aftermarket gauge going bad so its reading wrong. I am not sure how else to tell my oil pressure since i dont have a gauge on my dash. My car is running fine, and my oil is not leaking at all. Mine drops to 10psi after idling for a long time. I would like to take this in for warranty but need to test out to see if its jsut a bad aftermarket oil pressure gauge.

 

is that head or block pressure, cause 10-17 is normal for idle psi after warmup...

 

take your oil pan down and see if the sump screen is clogged up!!!

 

this is a good call...will do, although i dont want to waste my new royal purple oil

but would that explain why it is fine at start up but as the engine warms it gets to be low????