Hello everyone, I am new to the forum. I am sure there must be a post somewhere on this site about this but I could'nt find a solution. I have a 1999 Jeep cherokee Sport 4.0 that i bought last year and I am experiencing low oil pressure when I accelerate. My gauge reads 13 psi and sometimes lower.I recently changed the oil pump and sending unit before this happen. I checked my oil level and everything is fine I do not hear any knocking only a little lifter noise then it goes away...any suggestions?

 

What problems were you having that caused you to change out the oil pump?

 

Are you sure the pump and sender are good and functioning. NEW does not mean good. Are you sure the parts were installed correctly. If I did some work and my Oil Pressure dropped after the work I would assume I either made a mistake on the instal or the parts used were defective.

 

A guess would be that the OP had an indication of low oil pressure and changed the pump. He still is showing low oil pressure which might well indicate there is some problem other than the pump and sender. Hence my question.

 

I was getting fluctuating oil pressure , my mechanic changed the oil pump and the sending unit. Now when i accelerate the needdle on the gauge barely goes above 20 psi from 13 psi.

 

What oil pressure sensor was installed? A dealer (OEM) sensor or an aftermarket sensor?

Sounds like a defective sensor was installed, or the wiring to the sensor was butchered.

 

What does your mechanic say? If you paid to have this work done, the shop should be responsible for seeing that the unit functions properly. If you mess with it you may well lose your warranty.

 

CCKen , it was an aftermarket oil pressure sensor.
Pelican , I am taking it to him on Friday. The unit was installed about 2 months ago and worked fine until recently.

 

My aftermarket one lasted 3 months then pegged to the right. Got a MOPAR unit and all is good. Make sure you or they get one that's for the gauge cluster and not the light cluster.

 

Has anyone actually tested the ACTUAL pressure or is everyone just depending on the reading from the IDIOT gauge in the dash?????

 

EZEARL, they are differnet oil pressure sending units, one for the gauge and one for the light cluster?

93gc40, I have not tested the oil pressure. I am planning to have the mechanic perform that test.

 

Yep. When I did my lights to gauges swap I also had to replace the temp gauge sending unit and oil gauge sending unit.

 

I haven't but should. I'm due for an oil change soon and I do have a gauge.

 

What brand of oil filter are you using?

 

That should be the first step