Automotive Forums  Where Car Enthusiasts Go to Discuss Cars Online

Oil pressure gage flips back and forth from 0 to 80 lbs. is this the sending unit going out or the oil pump. Where is the sending unit located on the engine on a 5.3 Liter. I found what to me looks like a low warning sensor on the engine right in front of the starter. I unplugged it and the gage still does the same thing.

Any help appreciated...  

I have a 1995 GMC 5.7L engine. The Oil Pressure needle flips back and forth from 20 to 80 lbs. Is it safe to operate the vehicle? 260,000 km.  

It would be safe to drive if it is only a bad oil pressure sensor. On the 5.3 and the 5.7 The sending unit is located on the left rear top of the engine, behind the intake manifold mounted into the top of the block.  

The sender is located on the back of the engine left (drivers) side. It's between the throttlebody and the firewall, and screws into the top of the block. You can remove it with a 1-1/16" deep/thin wall socket and about 1/2 pound of flesh off the top side of your right hand. Seriously if I had to do it all over again, I'd hire it done by the pros. It will not only save you a lot of heartache and pain, but a lots of knee time asking forgiveness for all the name calling, cursing, and BAD attitude.

Hope this helps, tybee69-Savannah Ga.  

Chevrolet trucks have instrument cluster problems. The cluster should be under warranty until 100,000 miles. After that prepair to spend more than $500 to get a reman cluster from GM. You can replace it with a used one from another pick-up, Escalade or Hummer (all will fit),  but beware they all will fail eventually.