Oil fill cap leaking

So i drove my XJ home the other day from college which is roughly 90 miles of 70mph driving. I didn't have any overheating problems, temp gauge stayed center the whole time. I popped the hood to check oil and coolant at the end of my trip, and noticed that some oil had leaked out the top of the valve cover and out from under the fill cap. I have not been having oil pressure problems. Is this just that i need a new filler cap gasket, or is something more serious going on. Let me know what's up. ('89 xj with a 4.0 renix)

Thanks,

ECGTECH

i cant think of any part of the engine on my 89 doesnt leak oil.

could be a bad cap or the back ccv line/grommet on the valve cover is clogged.

Clean everything on top of the valve cover off thoroughly. Drive it and periodically inspect the suspect area to see if you can isolate the root cause of your leak.

mine seeps a little bit - even with a brand new cap and brand new entire CCV setup

Definitely check the CCV, including the little rubber "J" hose on the air intake side.

Made a 200 mile trip, and when I stopped for fuel the attendant (no self-serve in Oregon) said I had oil on the rear hatch glass.

This had never happened before, so I started checking and there was that little "J" hose fully collapsed, like someone had applied vacuum to it. Replaced the hose with an Autozone generic and cleaned the rest of the CCV--no problems since.