whittdiane60

I have a 2004 Grand Jeep Cherokee Laredo. The Oil pressure light goes down to 0 sometimes when I stop and the the check gauge light comes on. Once I take off it goes off? What could be the problem?

chrisdm4

Could be a gauge is messing up and may need a new one or your OPS is messing up and is not reading when you stop but I really can not see that happoning. Guys can he get that flashed and see if that would do it?

MellottN

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whittdiane60

Yes, oil is fine and just changed. This is been going for a while but don't happen that often. I have had it checked and no codes are showing.

whittdiane60

Sorry but I am a female! lol

whittdiane60

Sorry guys, I am a female! lol

zedpapa

sometimes the oil pressure sending can start to fail and read lower pressure than what is actually there. i have heard that the 4.0's can wear the main bearings enough to bleed oil pressure at idle. the first step is verify oil pressure with a mechanical gauge. spec is 13 psi at warm idle. if that is ok then check the sender against a known good one. if your pressure is lower than spec, the bearing clearances need to be checked. that means pulling the oil pan and visually looking at all of them. if the clearance is too high and the surfaces are in good shape, then usually you can get away with putting new bearings in that restore the proper clearance.

zedpapa

bembas221

could be the oil pressure guage sensor switch. i just had to replace mine on my cherokee and they are known to go shortly after an oil change. mine was $40 from napa...very easy to replace, took about 10 minutes

chrisdm4

40 really!? Mine was like 20 or so when i did mine

bembas221

yea and napa had the cheapest one!!

Guitrplyr423

i have a 99 with the same problem, theres a pressure sensor near the bottom of the block i think on the passenger side, the piece is made of plastic on the inside and thin metal on the outside, so when the motor gets hot and cools off the metal on the outside expands and contracts which causes the plastic on the inside to break, i havent gotten the part yet, but im pretty sure its an easy fix

whittdiane60

I have a find who works for NAPA. I can let him get it for me. I thought the same thing you all thought. Everyone I have talked to here and other places have said the same thing. I just wanted to get your opinions also. Thanks for all the advice. We will start with that but will also check on the other things mentioned. Thanks a lot guys!

rickybarth

its an easy fix i had to do mine but its expensive 120 for the oem replacement all you have to do is put teflon tape on it and its good

whittdiane60

I have seen two of you mention OEM and OPS. What is the difference? Where is the OPS and where do you put the Teflon on it?

rickybarth

you put the teflon tape on the treads on the sending uniot where it screws into the block