Firstly I'd start small, so remove the pcv valve and give it a shake . if it rattles then the value is moving freely and if not its stuck with open or closed. Both of which can cause issues, as stuck closed means increased crankcase pressure and this pressure will try to escape somewhere else ie rocker gasket, dip stick pipe, front or rear main etc. Stuck open means a oil passing thru the valve at partial throttle when ideally it shouldn't as the vacuum behind the throttle has dropped.
Then check to make sure dip stick is a snug fit, oil in play plugs holes, oil leaking externally of the can covers.