[mustangII460]

Typically once the wire screen ( Under the gromet ) gunks up it will suck oil into the intake.

I would assume without any screen or PCV valve it was doing the same thing..

Im betting someone used a larger hose to jam into the hole. Go getcha a smaller hose. Its probably loose on the intake side aswell.

From intake, Hose>PCV valve>Grommet>wire mesh thingy.

Once you take out the grommet, I use a long wood screw to get the screen out and clean/replace.