My 90 xj runs good, however there is oil all over underneath. The guy told me it had an oil leak previously and the oil is not leaking much at the moment.. i run it for half an hour driving come home and 2 or 3 quarted size puddles when i come back 8 hours later.

Im thinking it has something to do with the pcv valve the guy put in.. its a rubber hose leading straight to the valve cover instead of the valve and there is backflow like a mf in the air box.

I bought a tiny cold air intake looking contraption for the valves as the part is a dealer part as far as i have seen and i'l see how it works. I'l plug the intake box off. The backflow to the airbox was bad.. theres not just oil on the filter theres oil leaking out of the box. Could this be where the fresh oil is coming from?

 

The guy at autozone told me that the CPS on XJ's are very common to go out also.. any experiences with this?

 

A bad pcv valve will cause oil to leak. Also valve cover bolts work loose.

 

will it cause significant oil leak? i have only had a week the guy told me he changed the valve cover seal; that isn't leaking at all though.

 

as i was reading this thread i decided to go out and check the bolts. when i was fitting an 11mm over the forward most bolt i was able to turn it at least three full turns with my hand, all bolts were like that except the furthest back. check your bolts! and there is one hiding undeneath the rad hose.

 

fixed the PCV valve; cleaned underneath. not leaking anymore from what i've seen.

 

did you check the bolts anyway? I would. MIne were so loose im going to check them every service