Oil Pressure Increase

jeep
cherokee

#1

My wife was driving to school and noticed that the oil pressure had increased to 70 psi and maintaining that pressure. Could it be a plugged filter? Oil Sending Unit?



2001 Jeep Laredo


#2

Plugged filter could do it, how many miles since your last oil and oil filter change?


#3

~2000, using 10W-30 oil


#4

More than likely, it’s the sending unit…


#5

Do the old “put a mechanical test gague in it”.


#6

Once I get home from work, I’ll give er the old test method.
Thanks for the direction.


#7

I’d say sending unit. The other cause would be the relief valve at the pump seizing, That’s unlikely since it’s still slammed @ FSD (full scale deflection). The oil pump relief, while potentially working at cold start, would not allow the engine to maintain FSD at hot idle …even with 50 weight oil. The span between max pressure and idle HOT is too great.

The filter is also unlikely. The filter’s bypass valve is specifically designed to limit the restriction the filter can present to flow if the oil pump is in relief, and limit the pressure differential due to loading to protect the media. Your sender would have to be above the oil filter to perceive pressure elevations with the pump not in relief. The filter would be “stacked” on top of what the engine presented in terms of pressure development at the mandated (at that time) flow rate.

Change the sender. If the condition remains, get the relief valve/oil pump serviced before you blow an oil filter off of the engine. My money’s on the sender.