Need help. Oil pressure issue.

bfreeder0055 · July 20, 2015

I looked all over this site as well as others and can not find anything that pertains to what I am dealing with. I have a 09 Silverado Hybrid 6,0 4x4. The other day the check engine light came on and the oil pressure gauge pegged out at 80PSI. Pulled the code and it was for high voltage at the pressure sensor. I ordered a new sensor replaced it. Everything worked fine and I had normal pressure readings via the gauge and my scan tool. The next morning when I started it up it was back at 80psi and the light was back on for High Voltage again. Pulled it back apart and replaced the screen, and changed the oil and filter and still have the same problem. As soon as I turn the key to the on possition the gauge maxes out. When the sensor is not plugged in I get no reading as I should, but when I plug either sensor in it goes to 80 right away. While driving the gauge sometimes goes back to 0psi but the scan tool still shows max pressure. I do not get the chime and message that pressure is low even when the gauge reads 0. The truck runs fine and makes no noise and does not get and hotter, but the AFM does not kick in and it stays in 8cylinder mode the entire time. Talked to my local dealership and they said they never ran into one that didnot work when they changed the filter and sensor. I did on OHM test on both of the sensors I have and got the same reading on both of those as well as one off the shelf at Napa. Can anyone help please!!!

Duelin · July 20, 2015

You are going to have to install a mechanical gauge and find out exactly what the oil pressure is. If the pressure is still high with the mechanical gauge then you will have to trouble shoot your engine to find out what is causing the high pressure. On the other hand if the pressure is in the normal range then you will have to trouble shoot the electrical system that controls the oil pressure readout.

bfreeder0055 · July 20, 2015

It has to be an electrical issue because as soon as the key is turned on and engine off it reads max on the gauge and scan tool. When i unplug the sensor it reads 0 on both, but as soon as a sensor is plugged in it maxes out. Starting to think its the pcm because of this.