When stopped and in gear I see the oil pressure drop, warning comes on.

Replaced the oil pump
Replaced the Oil Pickup O-Ring
Replaced the Oil Pressure Sender
Synthetic Oil
New filter

Found a small crack in the pan so that was replaced also.

The old oil pan was pretty damn clean, even low in the sump, oil looked good too.

Gauge will go to about 30PSI when driving and the RPS are upward of 1500-2000 but when stopped at a light, in gear, idle around 750RPM, Oil pressure warning comes on and appears to be at about 10PSI.

No difference in engine performance, no noises. Not burning oil, plugs were clean, no smoke.

I am thinking maybe a clogged journal or a problem with the gauge? When these gauges go bad, they usually are pegged or at 0 all the time, so I am not sure that is it.

I am going to try and blow some air down the passage for the oil sending unit but hope someone had some other ideas.

2006 Tahoe 5.3 150K Miles.

 

Put a mechanical gauge on it. If it is showing more or better oil pressure than the gauge then the gauge is your problem.

 

That is my next step at this point.

I pulled the sensor and there was no screen installed, I picked up a screen for it and it doesn't fit which is strange, there doesn't seem to be any blockage as I can insert an 8 inch tool down the passage way. I verified that there was no screen installed with a scope so I am not sure why it lists one that doesn't fit. I started the engine without the sensor just for a sec and I get oil squirting out right away, clean flow, no debris.

I am going to hook up a mechanical gauge next and see what I am getting.