03 Nov 12, 09:54 pm
Research is a good thing. The 4.0 doesn't use a PCV system. Instead it is a CCV system. Basically no PCV valve. Both firings are just open. One has a smaller orifice. Both of mine are clear. So this is not the cause of oil in the intake. Next step is to check the baffles in the valve cover. If its not this then most likely caused by bad rings and valve seals.