jrocs00z28

iTrader: (1)

Hey what's up just a quick ? do you guys think my oil pump is going bad my check gauges light flashed today on my way home then i noticed right after that my oil gauge was a little past 40psi at 65-70mph and at idle was down to 25-30psi way below normal range. and yes before anyone ask my oil was and is full

RPM WS6

iTrader: (3)

25-30psi would not be low enough to set off the check gages light.

Not sure where you live so I have no clue what the outside temps were, but mine goes down to 30psi if I idle around in the summer heat. It always has. Granted, I also don't know if you have an M6 or A4 trans. The A4 cars have a lower idle speed (550rpm in gear vs 800 for the M6) so they show a little lower pressure at idle on average.

But either way you said that normally yours has always been at a higher psi? How much higher?

Check gages light will come on any time something in the gage cluster is out of normal range. The usual culprits are running low on gas or the volt meter dipping to low. Have you been keeping an eye on the volt meter? See if it dips down when the Check Gagaes light flashes.

Bird Man

iTrader: (1)

Did you check your oil level?

RPM WS6

iTrader: (3)

jmm98LS1

iTrader: (28)

Your oil pressure is in the acceptable range. Is it way lower than it used to be? Like said, check your other gauges and see if everything else is normal.

staringback05

iTrader: (8)

alright....once again, we have a low oil pres...THAT IS TO LOW...i take it by your name you have a 00z

a LT1 will have lower oil psi, just because thats how those blocks were made
a ported ls1/ls6 oil pump will run lower psi but its throwing out more volume so thats ok
BUT a stock ls1 pump should be puting out around 40 psi at idle and 60 at wot....any dumbass who tells you "your car can run with 10psi per 1000rpms" shouldnt own a fbody and they dont know there *** from a hole in the ground....my motor spun a bearing when my stock pump was putting out 25psi at idle....my new motor with new pump stays at 40...after 12k miles

IMO id get it changed

RPM WS6

iTrader: (3)

There are a lot of factors to consider here though. Under certain circumstances 25-30psi at idle might be ok. You have to look at the following:

- Oil used. As we all know, some oils are thinner than others even if they are rated at the same weight. I noticed a 2-3psi increase under most conditions just switching from M1 10W30 to M1 0W40.

- A4 vs M6. You might not think that the minor difference in idle speed between an M6 and an A4 would make much difference in oil pressure, but it is noticeable. When I used LS1 Edit to raise the idle speed on my WS6 from 550/650rpm (in gear/in park) to 800rpm all around (just like the factory M6 cars) I notice an instant jump in oil pressure by a few psi.

- Outside temp and type of driving. In regards to my stock Z28, most of the time, once the motor is warm I’ll see about 35psi when I come to a stop after driving in warm weather. But, if it gets really hot out and I spend a lot of time idling in traffic, it’ll dip down closer to 30. Once I’m back on open road again and the motor cools a bit, I’ll be right back to 35 at a stop.

- Load on the motor. When I run the A/C system in the summer time while idling through traffic I’ve seen the oil pressure drop to 25-30psi. A soon as I turn the A/C off, I’ll notice the psi go back up to 30+ at idle within a couple blocks of driving.

- Oil psi at idle is only part of the picture. Even when it’s hot out, and I’m idling through traffic with the A/C on and seeing my oil pressure drop to the 25-30psi zone, I also notice that as soon as I even rest my foot on the gas to move it jumps right back above 40psi, and with more rpm will rise from there. I don’t think anyone will ever lose a motor by having 25psi at idle. But if you’ve only got something like 45psi at WOT, then there’s a problem.

I’ve owned 3 A4 LS1 cars and they’ve all behaved in this same manner with the stock pumps. I did put a ported ARE LS1 pump in my WS6 when the cam went in, that raised psi by about 5-10 across the board.

My only real concern in this thread is that the original poster seems to be stating that he's suddenly seen a drastic change in oil PSI. That change is what worries me more than the actual psi he seeing at this point.

jrocs00z28

iTrader: (1)

yeah your right like stated before my oil at idle would stay at 40 and wot 60 so the sudden drop in pressure is what leads me to believe the pump is going and i might as well have them replace some more parts while they are at it because u can hear either a tap or a knock so something is screwed up now because of this heard the noise yesterday and did NOT drive the car since parked last night and i posted. car is just sitting around so i don't cause anymore damage

99corvette

iTrader: (12)

Well my cars acts just like yours, my car when cold, is at 40 psi, then when it gets really hot, it goes down to 20psi. If i get on it, it will get to about 50psi 55 max.

staringback05

iTrader: (8)

RPM....like i said before my motor spun 2 bearings at 26psi.....

i factored in several things, heat is the biggest issue, but my car gets hot right now...im running 5w30, its a a4, and it stays at 40psi on idle....

to many people get on here and give bad advice which hurts other guys in the long run....im not saying u are...but im just sick of people telling others..."low psi wont hurt these motors"...those bastards should be banned for stupidity.

99corvette

iTrader: (12)

well i am going to take your advice, and figure out why i have low oil pressure, because its better safe than sorry

RPM WS6

iTrader: (3)

There is no way you damaged any bearings at 26psi when you were at idle. If that was the case, my motor would have been dead years ago the first time that happened to me. My guess is your pump was failing to properly increase psi with an increase in RPM, and that would have caused your failure (something like 40psi at 6000rpm, etc.).

Again, 25-30psi at idle isn't going to break anything. However you really shouldn't see it dip that low unless idling in hot weather for a long time. What's more important is what psi you're seeing at higher engine speeds.

staringback05

iTrader: (8)

cmon now man, how are you going to tell me what happened to my car?....

it had 45k miles...oil psi steadily dropped over time, stayed at 25 at idle for about two weeks of DD until finally i was like screw this....dropped the pan...all kinds of crap, took the lower end out...6 and 8 looked like someone took sand paper to them...

it might not seem possible to you, but regardless it happened...not all lsx blocks are the same and neither are the oil pumps for that matter...the 98s and 99s had problems straight from the factory....im just looking out for others, its better safe then sorry....

if i havent experienced something, done it myself, or seen it happen....i wont put in my .02........UNLIKE thousands of people on here....rpm u usually give pretty good advice, but you gotta be a little more open minded

99corvette

iTrader: (12)

well im taking your advice, better safe than sorry, my oil pressure drops to 20!

RPM WS6

iTrader: (3)

I'm not doubting what happened to your motor. All I'm saying is, I've seen the pressure drop to ~25psi on occasion as well (hot outside, A/C on full), and if that was going to kill the motor than mine would have been dead years ago.

Again, it shouldn't be at 25psi all the time, but under certain conditions it can happen and not be an issue.

The big issue here is that the original poster has seen a significant change from what the usual readings are for his car. That's what concerns me more than anything. But that could also be due to a bad OP sending unit.

Being open minded is great, but you also can't worry everyone into changing oil pumps every time the needle dips lower than 40 just because yours had an issue. Yes, it's true that it shouldn't sit at 25psi all the time, but 30-35psi regularly with the occasional dip to 25 under harsh conditions is what I usually see. Most stock idle speed A4 cars won't make 40 or better once fully warm. I've owned and driven quite a few, and that's always been my experiance.

staringback05

iTrader: (8)

if his psi is moving around, i think id first check the pan to see if theres any damage theres no harm in dropping it down and looking.... that sending unit might as well be as hard to change as a oil pump....

99corvette

iTrader: (12)

A sending unit isnt near as hard to change as a oil pump. You can change the sending unit without taking the intake off.

staringback05

iTrader: (8)

i wasnt being literal, of course a oil pump will take longer....i was implying how the sending unit is a bitch....and YOU can change the sending unit without taking the manifold off?...hmmm send me a video onthat, cause ive never seen it done... i mean you can take that off with a big *** socket, and still leave the big black manifold sitting there?

RPM WS6

iTrader: (3)

He might be referring to a vette.

staringback05

iTrader: (8)

ahhhh okie dokie....i was about to say...damn, rubber arms