Have repeated P0305 and P0307 codes. Have switched plugs and coils to
other side of engine. Lately its just #7 cyl missfire. Plug appears to be setting in oil. There is oil from hex part of plug down to tip noticed after removal. If I blow air around plug first, then plug is completly dry after removal. May go several days before missfire starts again and then it may be intermittant at first. I replaced intake gaskets this summer per diagnoses by a shop to fix other codes. Engine is in 2000 Grand Marguis. I use this forum alot for my 1974 F100. Thanks for in help

 

It's leaking from the valve cover gaskets or the grommets around the valve cover bolts