Any help would be greatly appreciated! LOW OIL PRESSURE

[Donnie88]

I have a 2004 Tahoe LT months back I changed the oil pump because I got a low oil pressure warning. I know I should have went with a pressure sensor first but. I went with a high pressure pump and changed the o ring as well while I was at it. Cause I knew it had never been done on the vehicle. So after the pump changed and all It still chimes constantly with the low oil pressure warning. I changed the pressure sensor and nothing changed. I don’t know if the sensor was faulty or not. On the gauge cluster that reads oil pressure it is all over the place. Constants jumping around and the chime is ridiculous. Sometimes it will ding when I stop. Other times it will ding while I’m driving. Can some one point me in the right direction of what to do here. Thanks!

 

[PNWYukon]

Are you sure it is not your cluster? My '05 cluster went **** up really quickly after on gauge was wacky.

Use a mechanical gauge to check the oil pressure to verify that the cluster is not lieing to you.

The pickup tube could have a crack in it. There are a lot of possibilites.

 

[alpha_omega]

x2 on the above post. Cluster, Pickup tube and sensor would be my first thing to check. Your pressure shouldn’t be jumping around like that. You do have the proper oil viscosity and qty correct? Not being an ass, just checking all the bases.
Have you checked the plugs to see if there’s any “blow-by”? Pull the plug nearest the firewall and the one closest to the radiator (driver side). Send us photos if they are anything except clean.

*Below is only needed only if your cluster and the aforementioned checks out.*
-Do you have a catch can? Have you checked all of your hoses and fittings? Usually fittings will show other issues, but it can throw sporadic pressures as well. When was your last oil change (aside from the obvious pan drop - current mileage and miles since the work)-


Let us know what you figure out and shoot us some more details so we can try to help.

 

[Donnie88]

When I replaced the oil pump I went ahead and replaced the pick up tube and the o ring. Recently done and oil change not even 1200 miles ago. I run castrol edge 5w30 synthetic with k&n filter. I know my cluster may be a little weird sometimes cause my heat hand will still be up some even when the vehicle is off. Plugs checked this morning everything in that area looks wonderful. Sometimes the pressure wants to act normal sometimes it’s passed 80 and then it will sit below zero until I press the gas.

 

[Donnie88]

Note the oil pressure warning isn’t there until the truck is fully warmed up

 

[PNWYukon]

Get the cluster rebuilt and get a machanical oil pressure test done.

 

[swathdiver]

Get the cluster rebuilt and get a machanical oil pressure test done.

He could also add two or three quarts and see if its the o-ring again.

 

[Fless]

Wrong o-ring?

 

[ScottyBoy]

I'm having a very similar issue on my truck. I bought an oil pressure test gauge, but come to find out it doesn't fit with any of the included adapters. I need to order an adapter for LS engines in order to test the oil pressure. Then I will know if I need to replace my oil pump or not. Scared to drive it until then, because the factory gauge is only reading about 5psi. I replaced the sensor with a brand new NAPA sensor shows the same reading.

 

[afpj]

What brand oil pressure sensor did you use? Cheap aftermarket typically don't work on our vehicles.