pcv valve
 

Would an 89 xj have a pcv valve ???? I changed the air filter couple of days ago and there was a little oil on the corner in the air filter were the vacum hoses come into the air cleaner box. Thought it could be the pcv valve if they have one if not any suggestions as 2 why there is oil on the filter? This is strictly a trail rig and I rolled it on the passenger side on the last ride could this be a reason any help would be appreciated

it is ccv, rear most fitting on valve cover is a metered orifice that you can clean
edit: mine was completely clogged, little carb cleaner cleared it out

Thanks will this have some effect on performance of the motor???

only if it is clogged, if you read around about oil in the air box it is most often cuz of the ccv line is clogged, mine ran smoother after I unclogged mine.
as a result my intake was filthy

The CCV system is very suspect for clogging and failure on the 4.0 over time. That can result in some oil in the air filter box.

For the best results, pull the valve cover. Thoroughly clean it. Remove the grommets and replace all of them once the valve cover is cleaned, only around $45 for the CCV parts kit. (Napa/dealer) New valve cover gasket, install those new CCV hoses and your CCV system is now fully refurbished.

Your engine will thank you for it and will breathe as designed......!

If you still get oil in your air filter after performing the above, you most likely have true "blowby", which is worn piston rings. SEARCH for information about that condition.

But a clean CCV system is absolutely job #1.

Thanks for the info I will definetly do that this weekend