Low Oil Pressure 2013 ZL1

[evonschu]

Originally Posted by Batmanntexas

Just my $.02 here, but I don't believe your issue is from the relief valve in pump, as those fail in a 'Zero pressure' state. I also don't think the O-ring is a culprit, as that issue would have presented itself after re-assembly, not years later. If the oil pan has the relief valve, then I'd be willing to bet that it is not causing you issues either, as it is normally closed and only opens when pressure exceeds the spring pressure keeping it closed (50-ish psi).

If I read your initial post correctly, the low oil pressure issue started fairly recently, correct? If so, then I don't believe the issue would be that the pump is not supplying the enough volume/pressure, as you would have had the low pressure issue from the beginning (after the modifications).

Wrong oil viscosity would definitely exhibit this type of behaviour, but again, you would have noticed this directly after the oil change.

A faulty sensor might be the cause, but this can only be diagnosed either by swapping sensors, or utilising a mechanical pressure gauge to verify pressure.

Worn bearings (most likely cam) are probably the culprit here, unfortunately.

Good luck with it, and please let us know what the issue was.

-Scott

I actually don't know when this started. I only noticed it recently. Seems like the common consensus here is to get it mechanically checked first and rule out a sensor issue and change the oil as easier first steps. The info about the pressure relief valve and what would happen in some of the other problematic situations you listed is very helpful. Like I said it almost looks like if you add +10 PSI to whatever RPM the car was at it'd be normal. The fact that I do not notice any noticeable problems or noise while driving also makes me wonder. Hopefully it's not those cam bearings. After the upgraded cam and then years later the replacement cam from that failed lifter each from 2 different shops who knows. Will cross my fingers it's just the sensor and the actual oil pressure is fine. Might be a bit before I can get all this checked, but as soon as I do will for sure update this thread as I know how useful it can be for others.

[0stones0]

Originally Posted by evonschu

I actually don't know when this started. I only noticed it recently. Seems like the common consensus here is to get it mechanically checked first and rule out a sensor issue and change the oil as easier first steps. The info about the pressure relief valve and what would happen in some of the other problematic situations you listed is very helpful. Like I said it almost looks like if you add +10 PSI to whatever RPM the car was at it'd be normal. The fact that I do not notice any noticeable problems or noise while driving also makes me wonder. Hopefully it's not those cam bearings. After the upgraded cam and then years later the replacement cam from that failed lifter each from 2 different shops who knows. Will cross my fingers it's just the sensor and the actual oil pressure is fine. Might be a bit before I can get all this checked, but as soon as I do will for sure update this thread as I know how useful it can be for others.

Much appreciated. Too many times there are not follow ups.

[FasNuf]

According to the 2014 Service Manual for the LSA engine page 9-1418

Oil Pressure Minimum Hot
24 psi@1000 rpm
35 psi@2000 rpm
38 psi@3000 rpm

[Robmnrd]

Originally Posted by FasNuf

According to the 2014 Service Manual for the LSA engine page 9-1418

Oil Pressure Minimum Hot
24 psi@1000 rpm
35 psi@2000 rpm
38 psi@3000 rpm

I was hoping someone would post something like this.

Seeing some variety of PSI posts ITT and made me wonder about my own.

I live in TX - obviously things get hot-hot here - and I always wondered if it was normal/good/bad that the gauge always reads ~26-29 for hot idle pressure. Like if I go out when it's 105+ degrees outside and have some fun for a little bit, hot idle tends to hit ~26-27, then slooooooowly crawls back up to ~28-29 as things cool down ever so slightly. @1000rpm it's already rising to 31+ no matter the temp outside, so I guess I'm safe/healthy in that regard! (Keeping in mind the gauge is only pseudo-accurate of course.)

I've read here and there that if things are working correctly, the upper limit (by design) for oil pressure is like mid-50s or something, is that correct to your knowledge? It's kind of what mine does on the gauge - rises really quickly during the first ~half of the RPM band and then kinda just tops out for the latter half of the range with very minimal increase with a max (on the gauge) of an estimated ~57-60psi.

[evonschu]

Originally Posted by FasNuf

According to the 2014 Service Manual for the LSA engine page 9-1418

Oil Pressure Minimum Hot
24 psi@1000 rpm
35 psi@2000 rpm
38 psi@3000 rpm

Thank you for this info!!

[FasNuf]

Originally Posted by Robmnrd

I've read here and there that if things are working correctly, the upper limit (by design) for oil pressure is like mid-50s or something, is that correct to your knowledge?

The PRV in the pan limits pressure to around 58psi. I saw this on my LSA before removing it and installing a different pump. The PRV is used in AFM/DOD cars to limit the pressure to the special lifters used in that application. The LSA doesn't have AFM/DOD, but GM decided it wasn't going to make a special pan and part number just for the LSA.

Here is a video of the PRV on the LSA pan.

[evonschu]

I brought my ride down to the shop today that did the replacement Johnson lifters and cam way back. He hooked up his OBDII computer/tablet to it and could see the instantaneous oil pressure on there and was seeing consistently 5-7PSI above what the gauge in the cluster is showing. Idling in mid 20's for PSI and was about what FasNuf posted the service manual says it should be as he revved. He had some other things to work on today and was going to look into where that gauge is getting its data from and if there's an adjustment or what the fix would be for this.

I'm a little baffled because if the PCM is seeing the correct values for pressure, why would the gauge be showing lower. I know others have said the gauge is an estimate. Does that mean my gauge itself is messed up? Or how is the gauge calculating this "estimate". I wanted to add the X-Gauge codes to my scan gauge II's I have but the dam firmware is not new enough so I'm getting a replacement I'm going to swap it with so I can monitor it through that in the mean time. That'll be here May 14-16.

At least was reassuring there wasn't any actual oil pressure issues. I wanted to check the sensor itself regardless, but it looks like from videos that it's of course buried in the back side of the engine where I can't easily reach, that correct? But again, if it were the sensor itself then the PCM would also be seeing low pressure on his computer he hooked up, so a little perplexed.

Also, does our oil pressure sensor have a screen in it too? Concerned that might have debris in it from when the lifter went bad and that might be playing into this.

Let me know your thoughts. Thx!

[gtstorey]

put a mechanical gauge on it.

[joshnmn]

Always sound advice ^^

But, to answer your question- yes, oil pressure sensor behind the intake does have a screen on it. Also, oil pressure sensors fail all of the time. Just change it. Don’t know how hard it is on a LSA.

[evonschu]

So I finally got the codes for Engine Oil Pressure in PSI for LSA X-Gauge for my Scan Gauge II (See below if anyone needs it):

Engine Oil Pressure (PSI)
TXD: 07E0221470
RXF: 046205140670
RXD: 3008
MTH: 001D00320000
NAM: EOP


When I programmed it in, it does look like the gauge in the cluster is a little lower than what it was reading, but not by much. The Scan Gauge II readout still showing below what it should for various RPMs. See photos. Top Scan Gauge II - "OP" sensor readings at various RPMs. OP 33 was when engine was cold.

Going to get the screen and oil pressure sensor replaced as a next first step.

[evonschu]

The more I'm researching it the more I'm thinking it's the screen before the oil pressure sensor which I'm also going to have replaced:

https://www.mightyautoparts.com/wp-c...re-message.pdf

https://www.reddit.com/r/camaro/comm..._oil_pressure/ "Happened to my ls3. Turned out i had a lifter get stuck, ground the cam lobe, and got metal lodged somewhere in the oil galley. Got a melling oil pump and a cam swap with ls7 lifters"

^^ Had the same thing happen to me... I'm fully imagining pulling that screen out and having it filled with sludge or debris.

[gtstorey]

Don't drive it assuming the screen is blocked. May be, what if it is actual low pressure? It does happen.

[Joe.G]

Do LS3 or LSA Manual cars have the screen? I thought only L99 did.

[evonschu]

Originally Posted by Joe.G

Do LS3 or LSA Manual cars have the screen? I thought only L99 did.

I don't know for sure. The guy in this one youtube video I watched doing the repair on an SS had it. That's an LSA w/o the blower I assumed.