How high is too high? My kid says his XJ oil gauge goes up to 80 when he accelerates and drops down to 40 when he let's off.No codes yet, We just changed the oil and everything is topped off.I haven't seen it yet as it's like 20 degrees out , my XJ manual doesn't even show where the sensor is located.

 

I'd call it a good thing. however 80 does sound a little high to me, but what do i know im used to xjs that barely keep over 20

40 should be around normal

 

XJ oil pressure senders are not known for their honesty, verify oil pressure with a mechanical gauge, replace if the numbers are not the same as seen while driving. If you dont have one most auto parts store will rent you one free with their loan a tool program.

 

What weight oil are you using? 20 degrees will thicken the oil up quite a bit and cause the oil pressure to be high.

 

10w30...same as I run in my LJ. I'm hoping it's a bad sending unit.

 

The fact that you are seeing a change in oil pressure immediately after changing oil is likely not a coincidence.

The sending unit is located directly above the oil filter and it is easy to "bump it" when you are changing the oil filter.

I would perform an inspection of the connector on the sending unit, remove it and clean it with electrical contact cleaner and reconnect.

If that doesn't resolve it, buy a new oil pressure sending unit. And for best reliability and longevity, buy it DIRECTLY from a Jeep dealership. Don't take a chance on an aftermarket oil pressure sending unit. Too much crap floating around in that category.