Hey guys,


I had some wonky oil pressure readings going on, at idle it would drop down to zero, then up to 30ish when on the highway, so I did my homework, and ordered and installed a nice shiny new Mopar oil pressure sending unit.


It has worked fine, hovering around 40psi depending on engine speed and what not, but then all of a sudden (couple weeks after install) I noticed it's now just pegged at 80psi. Dead stop, on the freeway, no matter what, I'm at 80psi. Has my Mopar unit gone bad? After all my reading, I went with Mopar because it seemed they were the ones that didn't have problems, so I'm just worried I have some other issue now?


Thanks!
Scott

 

Go to the junkyard and get a few and test them out. I bought two from autozone and they both failed. Kept getting 0 pressure. So I ended up scooping up one from the junkyard which it worked.

 

Dang, JY... I spent a day there a while back and determined that I don't much care for that place lol. I may have to do that though.

 

Replace your failed MOPAR sending unit under warranty.

About the only other time they do that is if you have a direct short to ground in the oil sending unit wiring harness somewhere.

 

So if I get a warranty replacement and the same thing happens, should I be looking at my wiring harness that leads to the sender?

 

That Oil Pressure Sensor lives in a pretty hostile environment.


Make sure you didn't damage it changing your oil filter.


Examine the sensor connector for damage and security.


Examine the wiring going to , and at, the connector for broken or chafed wire(s).

 

Thanks CCKen! I'll check all of that. I just bought the Jeep not too long ago. When I did my oil change (among a bundle of other maintenance items), I replaced the sender at the same time, so it went in after the filter change happened. I'll check on the wires though, because that is a definite possibility. I figure I can also put a bit of dielectric grease in the connection to be sure that's getting good contact.

 

DO NOT use dielectric grease on any pin connector. Just look for corrosion on the pins and pin cavities then wash out using CRC QD Electronic Cleaner.


Edit: If you still have oil pressure indications you don't like, start the engine and have a helper sit in the cabin eyeballing the OP gauge while you wiggle the wire harness to the OPS - see if it jumps around.

 

Noted. Will scratch that idea. I have the electronic cleaner as well, so I'll give that a shot in addition to inspecting the wires.