Oil Pressure Not Building

[DropTopDon]

I recently replaced my rear main seal on my 04, and upon putting everything back together my check gauges light came on. This is two days after putting everything back together. I took it on a drive down to the grocery store once and that is it until this morning I see the check gauges light warning signaling no oil pressure is building. My RMS was leaking for about two months give or take, and I would try to add the oil lost the best I could. To my knowledge this could be due to a faulty oil pressure sending unit, or my oil pump has gone bad. Could these things have gone bad due to my RMS leak? Also is there a way I could diagnose it before I buy a new oil pump or sending unit?(I know not the most expensive replacements but keep in mind I'm 17 years old and my mom is not the most supportive of my at home repairs). Any help is appreciated, thanks.

 

[MutantNinjaTJ]

The rear seal being bad won't cause a loss of oil pressure unless you have 6 qts of oil on the ground under your TJ. When it's showing no oil pressure are the lifters making a lot of noise Indicating that you indeed don't have any oil pressure? Pick up a mechanical oil pressure gauge and screw it into the same threaded hole the oil sending unit is is and start it and read the oil pressure in PSI. Good luck, you have found a valuable source of TJ information here and I'm sure you will get all the help you need to maintain your Jeep. Mom will come around.......maybe!

 

[B34C0N]

Assuming that there is actually oil and you've checked, pulling the sensor is actually easy and fairly mess free. My landlord isn't too keen on "messy" work so this was still fine.

If you do replace it, use the end of a ziptie or compressed air to make sure no crud is blocking the hole to the sensor.

 

[cpwolf]

First off, awesome that you’re working on your Jeep, stay at it.

No to your question, just a RMS leaking drips won’t cause thes other issues, unless you let it leak all out and ran it dry. Doesn’t sound like that happened.

Most likely you had two back to back Issues. Or multiple things were wrong in the first place.

 

[Goatman]

Triple check you have oil in the pan. Many forget to refill fluids in the excitment of finishing up a project. If your good, then move on to electrical. Could you have pulled a ground wire off while under there? Check for good connections on any wires you may have inadvertently knocked loose. What is the gauge actually doing? Pressure reading lower than normal? No reading at all?

 

[SkylinesSuck]

Just theoretically musing on how replacing a RMS could cause oil pressure issues; you could have buggered up getting the bearing cap seated back down properly and that could maybe cause you to lose pressure. I would start with replacing the sensor or using a mechanical gauge to check first though.