2001 Jeep Cherokee Oil Pressure Gauge

J C TOBY

MEMBER
2001 JEEP CHEROKEE
6 CYL
4WD
AUTOMATIC
154,000 MILES

When my Jeep is being driven the gauge is right in the middle (40) very little fluctuation. When I slow down to a stop light it slowly goes down to about 20 or maybe a little lower if I have to sit a bit. As soon as I go it goes back up to 40 again. When the car sits and runs in park it runs between 20-40? This really only started about a week or so ago, or at least I only noticed it then.
Do you think it is the oil pump?
Thanks

1 Reply

JACOBANDNICKOLAS

MECHANIC
109,867 POSTS

Hi:
The pressure you described is normal. Minimum is 13 so you are well above that. As far as the fluctuation, that too is normal. In gear the engine runs at its lowest RPM which in turn provides the lowest pressure. In park or neutral, the engine will idle aprox 300 RPS's faster that will increase the oil pressure slightly. At operating speeds, the RPM's are much higher and the oil pressure will increase.

If you are concerned, you could have the oil sending unit replaced. It is located near the oil filter and just requires being disconnected and unscrewed from the engine block and replaced with a new one. That way you will be sure the pressure is good. The old one may be starting to leak and that will cause a change in what the gauge reads.

Let me know if you have other questions.

Joe