2001 Jeep Cherokee

2001 Jeep Cherokee V8 Four Wheel Drive Automatic 90000 miles

oil pressure drops to 0 when pressing accellerator when cold. Returns to 40 psi when returning to idle.
once engine warms, oil press stabalizes at 50 psi.
i use synthetic 10-30 oil and change filter at every oil change.
oil pressure sensor switch was defective and mechanic replaced it with an after market sensor, 2000 miles ago.
December 5, 2009.

Hi there, is this reading being taken with a mechanical gauge? If not have the pressure tested this way at cold idle, hot idle and 1200 RPM's report the readings here.

Mark (mhpautos)

Dec 6, 2009.
Thanks for your reply . The following: Thought about it and, since the pressure test kit is half the cost of the sensor, decide

Learned in the USAF that when you experience a problem, go back to the last thing that was done or switch that you tripped.
99 % of the time, that is the cause of your problem.
Oil pressure sensor switch was replaced 6 months ago when oem switch started giving perodic 0 psi readings.

I installed a new sensor and cleaned and wd-40ed connectors, new filter and synthetic 10w-30 Mobil 1 oil change.
Started it and all was back to normal.
Drove 160 mile roundtrip to Lake Tahoe and everything is still normal.

Thanks again and Merry Christmas from Northern California.


Dec 20, 2009.
Thats great, no problems, have a great Xmas

Dec 20, 2009.