Ever wash something with gas? We all have. Ever let it dry and see how much "film" is left on it? That film is conductive. Made up of left over hydrocarbons. Not burned off ash. Carbon is a conductor. All it needs to be is fewer ohms than the air gap at the plug and voltage will follow it to ground and not jump across the plug gap. The path of least resistance don't care about distance. From the center electrode to the ceramic to the shell. Less ohms is all it wants. Try some new plugs like Dave said. After it starts you can put them in one at a time and they will get better. Then you have a spare set. Yes I am cheap. That is not a crime. smile


Steve H