I have an 03 Sierra with a 5.3L V8 and recently my oil pressure gauge constantly fluctuates from Max PSI to 0 with no oil leakage anywhere. I just changed the oil in it recently but this still happens. The engine doesn't make any funny noises at all but the 'Low Oil Pressure' Alert light does come on and and goes back out as the pressure goes back to Max PSI. Has anyone else experienced this? If so, what was the problem? Any help would be greatly appreciated guys!!!

 

I was gonna suggest getting a new gauge but as I read your post further I would have to believe your oil pressure sending unit has failed.

 

That is what I was thinking but just wanted to make sure before tearing it apart ya know. Thanks for the reply!

 

Yes that is the quick cheap start. Good Luck.

 

I have this exact same problem with my 2003 silverado
i have changed the sending unit twice ,using an oem part
and the problem still continues.
Gm tech has made a few checks with the scan tool
and its not the gauge
truck has to go back for more testing and trouble shooting
any help would be appreciated.
Thank you
pmz20

 

I was wondering if it's a wet gauge or an electronic gauge. If it's still an OEM gauge it would be an electronic gauge so I would have to say the sending unit has failed. If it's a wet gauge.. the line may have some crud in it causing it to begin to plug