Hey all,
Ok I have had this happen to me once before and when I took it in to the dealer my trusted mechanic did an oil change and told me there was no issues.

Basically the other day I was driving and the "low oil level" on the DIC showed. The oil life still shows it is good (not that I go by that anyways)
I checked the display on my HUD and it showed half the amount of oil in there. The oil pressure gauge was reading 40ish and so I pulled over to investigate the engine. I pulled the dip stick and say that the oil level was in the cross marked area but not to the top.... maybe about half way down. Ok, so I add a quart......
The light disappears for a few then it comes back on.
The gauges also registered the low oil level, but then showed it back to the mid line.
Pressure still at 40ish.

Now understand I dont have an oil leak.... or at least one that is visible... and I jacked up the car and things look pretty clean in the engine area. I didnt check the sensor, which I kick myself for because I had her up in the air. Given, the readings tend to correlate to what I saw on the dip stick... sorta.....
So I will probably be under her again this weekend

Anyways...

Ok, so I add another quart.
No DIC warning about low engine oil, and the oil level on the HUD shows me that she is about 1 maybe 2 bars up from the midline again. The visual check of the dip stick shows me she is a tad over the top of the cross marked top line.
Oil pressure is now showing between 37-45ish (when before she was right at 42-47ish), and if I hammer on her the pressure goes up into the 50s maybe almost 60 (which I didnt notice before when I drove.... but honestly I didnt watch the gauge as much because I figured why should I when it was ok when I looked at it and didnt see any engine lights)

Could this be the sign of a bad pump?
Could this be the sign of a bad sensor?
What do you guys think it could be?

The DIC shows no codes in it

My car is an 99 LS1 running a supercharger and only has about 66000 miles on it.

Any help is appreciated

 

Back when my 2000 was 2 yrs old and 14000 miles my oil pressure gauge showed 0 and I turned the engine off. Fortunately I was at an event had had my Son-in-Law put my car on his trailer and drove it to the dealer. Turns out GM had a silent recall on the oil pump and they replaced it under warranty. When the pump goes, oil pressure stays at 0, so yours sounds like a sensor.

 

Ok, maybe I am not understanding but I have never seen an oil level on the HUD. I see oil pressure represented in bar form when you are showing MPH and Tach. And if you get a little low then the check gauges comes on and they show the low level warning. If you are running those oil pressures and no warning lights because your full of oil what is your concern? Are you thinking that the HUD display of the oil pressure is showing you the level/amount of oil? If so, I believe you are incorrect.
Chris

 

WOW!!! I was thinking the same thing!! There no way that the HUD can display an OIL LEVEL.

It shows OIL PRESSURE in a bar graph.

BC

 

Cutlassmaster /Bill Curlee,
You are right. I mistaken the HUD oil indicator as a "level" indicator all this time and not a "pressure" indicator. I guess because the HUD shows a gas level.... I assumed the oil display was a level too.

OK, but the issue is the same
Oil level warning came on the DIC... Oil added.... it is now not on any more, but the dip stick level is above the cross marked section... Oil pressure when idle is 35-45... under hard load (me really hammering on the car) it peaks up to 60s... no oil leak seen so where is the oil going?
Could there be a bad pump? A bad sensor?
Are these all normal?
Like I said this is the second time this has happened but the first time I really looked into it, since the last time was on the interstate and I just pulled over and had it towed to the dealership, which told me there was nothing wrong with it. This time I am trying to understand more about this

Gordy M,
You are also probably right. Given, I am not sure if the pump is electric or mechanic and if this might be an intermittent problem.


Any advice would be appreciated

 

Probably just a bad connection on your oil level sensor, or bad sensor, clean it and see if the low level stops randomly showing up.

 

My light came on once and I was about a half quart low. So you probably added too much oil. It should not hurt it. Your pressures seem normal to me. If low oil light comes on and you verified on the dipstick that it is not low then there are probably some ways to test the oil level sensor (not to be confused with the oil pressure sensor). I would not sweat it if oil level is full and I had good oil pressure. Hope all of this helps.
Chris

 

If the oil level goes down and there are no visible external leaks, then the oil is either going into the intake manifold via the PCV system, or the oil is getting past the rings and/or valve guide seals. In all cases, the oil would be getting into the cylinders and burnt up.

LS engines do use some oil ... typically about 1 qt every 3~4K miles based on how it driven. How often are you adding oil - how many miles between adding a quart?

 

Well I wasnt aware that the LS burns some oil.
This is the only time I have ever added any oil to it.
Normally I never have any issues or lights.

As for the pressures, are you sure that it should climb like that under a load? I mean a moderate to hard acceleration and it jumps up to 60 psi. And at idle I am seeing 40-43 when warm, but 35-43 when cold.

I guess I am worried that I could end up in a situation I was in when I was first starting to drive, where I ended up throwing a rod due to a lack of oil. Given I am much older now and know more, but that experience left a bad memory and so I dont ever want that again.

So to confirm with you guys, there is no oil level indicator? Just a oil pressure indicator on the vette HUD?

I appreciate your answers

 

Since your engine is supercharged, it might burn more oil than if it wasn't. Supercharging can cause more pressure to blow by the rings and cause more oil to go out the PCV system. You have an oil catch-can on it?

Perfectly normal. These engines have a positive displacement oil pump. So at idle with hot oil you should see ~28 to 30 PSI, and for every 1000 RPM over idle you should see ~10 PSI increase.

Keep an eye on your oil level. Doesn't hurt to check it often and get a feel for how much is burned.

It has a LOW OIL LEVEL warning system. A LOW OIL LEVEL message displays on the DIC and there is a warning chime.

Go here and download the 1999 Corvette Owner's Manual and read it.

http://www.corvetteactioncenter.com/...99corvette.pdf

On page 6-12 it says:

"If the LOW OIL LEVEL message on the Driver
Information Center comes on, it means you need to
check your engine oil level right away."

On page 2-104 it says:

"LOW OIL LEVEL: Press RESET to acknowledge that
you have read the message and to remove it from the
display. The message will reappear every 10 minutes
until this condition changes.

You will hear two chimes when this message is
displayed. If this message appears after starting your
engine, your engine oil level may be too low. You may
need to add oil. See “Engine Overheating” in the Index."

 

Zee O,
Thanks for the info. I figured that was everything that I was thinking, but just wanted to make sure since my past experience with a engine with no oil. I just that and just the way my luck has been running lately.....

To answer....
No Catch can
Is it really necessary or a better thing to have?
What is the plus to having one?

And I guess my other question is what is the "bad psi" or "red zone" to watch out for with oil pressure? I know I have heard people hurting there engines under high oil pressure.

Thanks!!

 

Yes, a catch-can makes a difference on how much oil is sucked into the intake manifold. Do a search for catch-can and you'll find 1000s of thread about it.

Like I said earlier, normal oil pressure is usually ~30 PSI at idle when hot, and ~10 PSI for every 1000 RPM above that.

So,
Idle = 30 PSI
2000 = 40
3000 = 50
4000 = 60
5000 = 70

The oil pressure will remain about 70 for RPM above 5000 since the pump is usually in pressure relief mode around there.

 

big thanks all