I pulled the upper plenum because I'm changing the valve cover gaskets and found the inside was coated with some oil. Now I recently pulled the plenum about a month and a half ago and found no oil, just crud which was thoroughly cleaned. Is my PCV valve malfunctioning? It's definitely coming from the crankcase because when I pulled the hose from it it was pretty saturated. I changed the PCV about a year ago and recently have noticed lower oil level then normal even with the valve cover leak.