Not sure if I'm posting the right place but here's my question I was towing a trailer with my 98 xj and when I was sitting at Idol my oil pressure would drop to 0 but under normal driving it was at 30 what does this mean. Please help.

 

Make sure oil is reaching the top of your engine at idle, you can take a peak under the oil filler cap.

Verify these readings with a mechanical gauge. The oil pressure sending units on XJs are notoriously prone to failure.

That said, the oil pressure specs are: 13psi and above at hot idle and 37-75psi when above 1600 RPMs.

 

Hmmmm I know it leaks. But that's the 4.0

 

It means if you will be gentle with the old lady she may last a long time.
Mine has been doing that for years.

 

Should I worry

 

Not if a mechanical reading is within spec.
I never trust the dash gauge to be accurate, I only pay attention to a sudden CHANGE in pressure, that could indicate trouble.

 

Sounds like old age. Is it knocking? When the gage is reading zero look under the oil fill cap and see if any oil is flowing...if so I wouldn't worry too much unless your willing to rebuild. How many miles? Change oil & filter. What kinda climate do you live in? What was your engine temperature when towing? What was your idle speed? We need data to analyze.

 

Ok maybe ill change the pressure sensor and see whats up. Im using full synthetic is that ok

 

What weight? Usually synthetic will lower pressure when compared to same weight dino. Pressure ain't everything,flow is.

 

10-30

 

Still waiting on more info. Too many variables to give an answer.

 

Meaning