Weird 99 LS1 Oil issue!

**kevamg** · 03-05-2012, 12:30 PM

Had the oil changed.

Took the car out for a cruise Saturday night never went over 2.5k RPMs.
Oil pressure starts to drop to 20 PSI at idle and fluctuate between 20-30 PSI. Next thing you know the guage bottoms out and check gauge light comes on.

I shut her down really quick.
Check under car no oil no smoke not even a smell of oil.

Let her sit start her up and the valve train is clicking as in not being lubed. The oil pressure stays at 45 PSI and eventually lube the valvetrain again and the clicking stops and the engine sounds quiet.

I park the car and leave her alone for the weekend.

Went out just now started her up and she runs just fine at 45 PSI at idle quiet as a mouse drive her around and oil fluctuates between 40-50PSI under 1.5 RPMs.

What the hell is up with this car?

Could it be the oil pump ready to croak? How could something mechanical give intermittent issues?

The guy who did the oil change not put enough or maybe too light of oil in her?

A crappy filter not installed correctly?

Also upon further inspection of the engine bay I noticed this line is ripped and disconnected.
Could this be the culprit?

**cammed goat** · 03-06-2012, 05:27 PM

That be your issue right there. Those hoses wear over time and cause issues like you described. Both air and oil pass through that hose. Others will chime in with their remedies and suggestions.

**cammed goat** · 03-06-2012, 05:35 PM

Try this:

http://www.ls1.com/forums/f6/pics-pcv-hose-fix-145574/

**kevamg** · 03-07-2012, 10:59 AM

$15 Fix!!! Thanks alot goat!

***SMWS6TA*** · 03-07-2012, 12:08 PM

PCV leak doesn't explain the sever drop of the oil pressure. Vacuum leaks will cause idle issues and hesitation, but NOT oil pressure dropping to zero.

Ask Jodi, her oil pressure dropped like yours and it ended up costing her new engine, she is now on engine # 3 in less then 3 months.

I'd start shopping for a LS6 oil pump and begin planning on swapping it.

**Smittro** · 03-07-2012, 02:54 PM

Originally Posted by SMWS6TA

PCV leak doesn't explain the sever drop of the oil pressure. Vacuum leaks will cause idle issues and hesitation, but NOT oil pressure dropping to zero.

Ask Jodi, her oil pressure dropped like yours and it ended up costing her new engine, she is now on engine # 3 in less then 3 months.

I'd start shopping for a LS6 oil pump and begin planning on swapping it.

Agree..

Definetly sounds like something up with the pump.

To the OP,, if the top end is/was making noise the bottom end is likely not getting the oil it needs either.

I would NOT run the engine any further, starting it up just to look @ the guage could cost you your engine.

**kevamg** · 03-07-2012, 03:27 PM

LS6 Oil pump ordered along with new A/C compressor.
Mine as well keep the car now.

**cammed goat** · 03-07-2012, 03:36 PM

Keep us posted with progress.

**kevamg** · 03-07-2012, 03:43 PM

What's a good price for an LS1 rebuild anyway?
I was already quoted $800 for the oil pump installation.

**cammed goat** · 03-07-2012, 04:01 PM

Prices vary between shops as every shop has their own set labor rates.

**flybird** · 03-07-2012, 05:46 PM

Depends on rebuild, if a FULL rebuilt engine meaning new longblock and up, $4000 +, if its just a top end build, then about $2000 +...

You have a v8 so it will be more expensive.

I got my whole engine done, longblock and everything, done for $3200. This is a 3.8 so..

**kevamg** · 03-07-2012, 06:18 PM

Crap man $4k+ is brand new crate engine range.

**pajeff02** · 03-07-2012, 06:19 PM

Oil pump is not a difficult swap, just time consuming and if you don't drop the oil pan completely the bolt on the pickup tube can be a challenge. Personally, I would want to check the pickup screen for debris and not just throw a pump on it and hope for the best.

**flybird** · 03-07-2012, 06:22 PM

Originally Posted by kevamg:2753994

Crap man $4k+ is brand new crate engine range.

Yes thats the price of a FULL engine build. You basically have all new parts therefore its a new engine...

Im with jeff, he knows his shit and great with knowledge.

**flybird** · 03-07-2012, 06:25 PM

Also $800 for the labor???
find another shop..

**jrbonds** · 03-07-2012, 07:16 PM

Originally Posted by SMWS6TA:2753835

PCV leak doesn't explain the sever drop of the oil pressure. Vacuum leaks will cause idle issues and hesitation, but NOT oil pressure dropping to zero.

Ask Jodi, her oil pressure dropped like yours and it ended up costing her new engine, she is now on engine # 3 in less then 3 months.

I'd start shopping for a LS6 oil pump and begin planning on swapping it.

Yeah, don't reuse old oil pumps. Its cost me outrageous amounts of money in the last six months.

Get a new oil pump, find a friend that is mechanically inclined to do it for you, or local members of ls1.com. But I highly suggest to not drive your car until you fix it. I went 6 miles after the oil pump screwed up and spun a bearing.

***SMWS6TA*** · 03-07-2012, 08:28 PM

OP one more thing to check and I say this in a way that you might be one of the very lucky ones.

Reach behind the intake on the drivers side. There is a plastic piece that has a wire harness on it. This is the OPSU. You could have a crack or bad OPSU. Again it's a very long shot, but worth a check to see.

But my money if on the oil pump.

Here is what it looks like, the one with the green top: