Originally Posted by cobalt327
Check and see if the PCV valve vacuum hose connects at or very close to that intake runner. If the valve is bad or there's a lot of blow-by, that'll oil up that plug and combustion chamber pretty good. I'd replace the PCV valve and see if there's an improvement.
A new set of plugs would be nice, but just swapping out the oily one for a different plug will let you know if there's an improvement. Clean the oily plug w/carb cleaner if you have any on hand. Otherwise, using it in a different cylinder should burn the oil off if it's not too bad.
PCV valve connects to the front of the intake and the fouled plug is at the very rear. Ill check the pcv valve but i think its ok. Plugs are only a year old, and that particular one has been replaced one since then when it stopped firing for no reason.
I suspect this cylinder is not firing much or at all and I think its an injector problem (plug is wet, cruddy, and black, but the cylinder has compression and the plug fires when laid on the engine and connected to the plug wire, but the engine doesnt run any smoother or rougher with that plug wire disconnected) so I am working on pulling the intake and injectors to clean them right now.