Oil around sparkplug = valve cover gasket leak?
I've had a very slow leak, no noticeable oil consumption, just an occasional smoke puff from oil hitting the exhaust from time to time. Oil appears around the edges of the valve cover.
Today, I took off the engine cover to investigate a little closer and noticed some reflection around the sparkplug to the right of the valvetronic motor. Pulled the coil from that plug and the one next to it. There appears to be oil around the sparkplug on the immediate right of the valvetronic, but not on the plug to the right of the "oily plug" (see pic).
So, I'm wondering... is this a for sure sign of vcg leak? Could it be anything worse? or could there be any chance it's oil filter housing? I've found some grime around the oil filter housing but no obvious trail or oil seeping.
Any thoughts or comments are appreciated.