L92 low hot oil pressure at idle HELP!!!!

[rdezs]

Keep in mind any device you plug in to read the oil pressure, is reading it off the same oil pressure sending unit your dash gauge is using. So if your dash is reading lower than your device plugged in, you probably need a new stepper motor in your instrument cluster. That's a pretty common issue in GM clusters. Rebuilt clusters with new stepper motors and LED lights are readily available and not too expensive. I have a local guy that does a mobile service and it takes him about half an hour to replace all the stepper motors for around $150.

Hopefully since you changed the valley cover, you replaced the oil pressure sending unit while you're in there?

LSX Oil Pressure Sensor Relocation Kit https://a.co/d/h30NSnG

But due to age and mileage, I would do the o-ring regardless. It's more of a maintenance item on the lS engines at this point.

 

[Jakob0327]

Keep in mind any device you plug in to read the oil pressure, is reading it off the same oil pressure sending unit your dash gauge is using. So if your dash is reading lower than your device plugged in, you probably need a new stepper motor in your instrument cluster. That's a pretty common issue in GM clusters. Rebuilt clusters with new stepper motors and LED lights are readily available and not too expensive. I have a local guy that does a mobile service and it takes him about half an hour to replace all the stepper motors for around $150.

Hopefully since you changed the valley cover, you replaced the oil pressure sending unit while you're in there?

LSX Oil Pressure Sensor Relocation Kit https://a.co/d/h30NSnG

But due to age and mileage, I would do the o-ring regardless. It's more of a maintenance item on the lS engines at this point.

I am definitely going to as well as plugging the AFM oil pressure bypass valve in the oil pan itself. I did replace the sensor as well.

 

[Charlie207]

How many miles on the engine?

 

[mickier]

I'd run some STP (thick type oil additive until you find the problem though

 

[Smulvey585]

I just changed to 15-50 Mobil 1
It’s warm weather now.
The startup psi=52
The warm running is + 30 psi

No more ticking in startup

I have a 6.2. 2014 98,000 miles with the AFM intact.

 

[Actifenpleinair]

2007 yukon Denali L92 with 277,000 miles, 5w30 synthetic, 6-7500 mile change interval, UPF63R filter, since 160,000 miles purchased w/ 6L80 rebuilt
i had lowish oil pressure at hot idle in gear, ~13psi. Internals and VVT all stock
Used my Banks Automind tuner to raise P and N idle to 700 R,D,M idle to 600, hot oil pressures of -19 psi, highway ~2000 rpm hot 30+psi. Seems to keep from low oil pressure and stalling. IDK, seems simple, what are your thoughts?
Lou

 

[Geotrash]

2007 yukon Denali L92 with 277,000 miles, 5w30 synthetic, 6-7500 mile change interval, UPF63R filter, since 160,000 miles purchased w/ 6L80 rebuilt
i had lowish oil pressure at hot idle in gear, ~13psi. Internals and VVT all stock
Used my Banks Automind tuner to raise P and N idle to 700 R,D,M idle to 600, hot oil pressures of -19 psi, highway ~2000 rpm hot 30+psi. Seems to keep from low oil pressure and stalling. IDK, seems simple, what are your thoughts?
Lou

It's a bandaid, but if it works...

The root cause is likely the oil pump pickup tube o-ring, but it's a bear to replace because you have to drop the pan. Could also be worn cam bearings, but my money is on the o-ring.

 

[rdezs]

Definitely a Band-Aid. I would also shorten your oil change intervals to no more than 4,500 miles.

I'd put my money on the pickup tube o-ring, a weak oil pressure relief valve in the oil pump.... It's probably collected it's share of crud over the miles.... And your first two cam bearings. Treated nicely, more frequent oil changes, it could last a week or it could go another hundred thousand miles

 

[j91z28d1]

2007 yukon Denali L92 with 277,000 miles, 5w30 synthetic, 6-7500 mile change interval, UPF63R filter, since 160,000 miles purchased w/ 6L80 rebuilt
i had lowish oil pressure at hot idle in gear, ~13psi. Internals and VVT all stock
Used my Banks Automind tuner to raise P and N idle to 700 R,D,M idle to 600, hot oil pressures of -19 psi, highway ~2000 rpm hot 30+psi. Seems to keep from low oil pressure and stalling. IDK, seems simple, what are your thoughts?
Lou

I like it.. it's at 277k, it owes you nothing.


you could test the o ring with the over fill with oil and face down hill and see if the pressure comes up.

 

[Campie]

Hard to give a definitive answer as it could be several things. If the valley cover and new gaskets doesn't improve it my guess is it is probably the O-ring on the pickup tube.

The easiest way to diagnose this is to over fill the crank case by about 2 quarts and park the truck with the nose pointing down hill, like nosed into a ditch, and see if the low oil pressure improves. I wouldn't run the truck like this for an extended period of time but for testing purposes it won't hurt anything.

You didn't mention how many miles were on the engine, but with it being an '07, if it hasn't recently had the pick up tube O-ring replaced, then that is the most likely culprit.

How difficult is it to replace that o-ring?