I had my oil changed 500 miles ago and the oil pressure gauge went from a little over 40 to now pegged at 80. Today the check engine light came on. Other than take it to a garage, any suggestions on what it is or what to replace. My dad suggested the oil sending unit and I have seen many people suggest that is very breakable in newer models.

I have a 2000 Jeep Cherokee sport
4x4
4.o inline 6 cylinder.

Thanks in advance.

 

You got it. First place to start. My old '91, it was as simple as re-seating the connector. Physical damage to the sending unit from careless mechanic monkeys is a common problem.

Pretty soon you'll find it better just to do your oil changes yourself (and how easy it is on an XJ)

 

I agree with the above on the sending unit. I would suggest you get a code reader and check if anything else is going on as well. If you haven't got a code reader yourself, I believe the likes such as Autozone provide it as a (free?) service.

Better safe than sorry.
Jeroen

 

Yes all the idiot auto parts store's Will let you borrow the scanner but now you do it yourself cause of insurance reasons,( I think it's just cause they are stupid) but your better off to do it yourself so they don't break anything.And yes swap out the sending unit , but get a good one from the dealer.

 

Almost assuredly the oil pressure sending unit, located directly above the oil filter.

Buy one from the dealer for the best reliability/accuracy/mating with your factory gauge. Worth the extra money.