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Oil build up around CCV hose connections on valve cover


NAXJA Forum User
Boston, MA
I've got a 99 4.0. I just noticed the oild build up the other day and wondered if it was indicative of anything. The air box is clean and everything seems to be running fine. Just hadn'tnoticed any oild building up there before.

Yes I ran a few searches. I found some stuff, but not exactly what I was looking for.
Mine's doing the same thing. And it's not blow-by. The air filter is spotless. That was the first thing I checked in a panic thinking it was the problem. but then I remembered the Newer 4.0's didn't really suffer from that problem.
It is just oil making its way past the fitting. Unless it is a large amount, it is nothing to worry about. If you want to solve it you might try something I did. Take the hoses off the top of the crank case and run a very thin layer of RTV. Makes a small gasket that really slows down the seepage.
I just had it off a couple of weeks ago to change the valve cover gasket, and i don't recall seeing it plugged up.