My oil pressure gauge seems to be malfunctioning. I understand that I should use a mechanical gauge to make sure the pressure is where it's supposed to be.

I've borrowed a pressure gauge, and now it's time to remove the oil pressure sending unit, however I can't seem to remove the electrical connection. It just seems to be stuck on there.

I don't see any sort of clip to press or remove. Is there some sort of trick? Or does it just require a firm pull? I don't want to break anything. Any suggestions would be greatly appreciated. Thanks in advance.

 

There's a clip that you have to push down on. It's there, keep looking. It does take a little force sometimes.

 

On mine (2000 xj) I believe there was a red locking tab that you need to pull/push in one direction to unlock it, and then typically with those clips you squeeze one part of it and it should disconnect, but they usually require a decent tug.

You should be able to rotate the sending unit by turning the brass hex fitting with a wrench, which should show you the other side of it, shouldn't be a big deal on the wire as long as you don't twist it too much.

 

I was able to get the wiring harness off, although mine was missing the red locking clip.

I then noticed that oil is leaking from the sending unit and the wiring harness has oil on the electrical contacts. Any suggestions on how to clean it? I'm thinking of just using electrical contact cleaner.

 

I would try using cue-tips or cleanex or paper towels to absorb and wipe up the oil, i wouldn't try spraying any sort of cleaning solution on it.

 

Thanks. I will try that first. I went ahead and ordered a replacement Mopar oil sending pressure unit since I noticed the old one was leaking. I will hook up the mechanical pressure gauge tomorrow to verify I have correct pressure while I wait for the part to arrive.

 

They leak. The trick that you can rotate the fitting above is how to get to it.

Isopropyl alcohol is always fine for these kinds of electronics cleaning.

 

Get a spay can of CRC QD Electronic Cleaner from an auto parts store and use it. It won't damage plastic like Alcohol or other cleaners.

 

Agreed. Works good. Cleaned all my injector connectors when I upgraded to 4 hole ones. Little pricey but the stuff to buy.

 

Worked great. New OPSU installed and oil pressure readings are back to normal.

 

Isopropyl alcohol is always NOT fine for these kinds of electronics cleaning. Many circuit boards have materials that are affected by isopropyl alcohol.



Ken's advice is the correct advice.

 

Word.

I figured he meant the ON engine device itself - just getting oil and crap off of there. Isopropyl wont seep into the cracks and hurt anything, itll dry up.

 

I use cheap Mall Wart starting fluid for allot of cleaning. Cuts and blasts away crud then evaporates pretty quick. But then I put bearing grease all over and in my battery connections, Dex III in my power steering and Castroil 30W in my engine, soapy water in my windshield squirter, LP in a tire in a pinch, and run propane in my AC as well. Go figure! All works fine since it's not nutty cold here.

 

What unit does everyone use? Just bought a 90 reads 0 on the gauge looking to replace the pressure unit and no auto parts store stocks it. Cheaper online anyways but I'm not sure what one to use. Part #? Please thanks guys.

 

The temp switch at the rear of the head that works a gauge? I did some searching at rockauto.com The one for a light is just a switch, where the one for a gauge is a variable resistor. They don't seem to clearly state what they are selling though! In the info on the $23 one they mention "variable resistor" though. I suppose you could call them. > http://www.rockauto.com/en/catalog/j...+/+sensor,4748