high oil pressure ?

2000 XJ 6cly. Changed the oil, and used 10-40 instead of 10-30 by mistake. Immediately noticed oil pressure of 80 PSI, even at idle. Change oil after 10 miles, to 10 - 30, did not change oil filter agian. Driven a few miles, shut on and off 3 times. Still showing 80 psi at startup, run, and idle. Was going to replace oil sending unit, $53 for part...

Advice? Thanks

You can replace the pressure sending unit,they are famous for reading incorrectly.I suggest testing with a manual guage to verify that is the problem, but theres a 80% chance its just the sender.

The sending unit for the oil pressure gauge works on resistance that increases when the oil pressure goes up, so an open circuit = infinite resistance = oil gauge constantly pegged at max.

Either you swapped gauge clusters from idiot lights to a full guages w/o replacing the sending unit for the gauge type or the sending unit is bad. But the most likely scenario is that you disturbed (disconnected or maybe broke)the connector or the sending unit taking off the oil filter, the sending unit is in a vulnerable spot above the filter.

First try cleaning and reconnecting the connector. $53 also sounds like too much for a part that is easily obtained at a store like NAPA.

yeah, i will check connection first. got that price from kragen auto store. thanks.

well, it stayed at 80 after the first check of the connection. but the wife just took it to the store...and wahla! back to normal.

Yup, pegged @ 80 is a certain sign that the sender is either unplugged or someone used thread sealant on the sender body.