Being somewhat obsessive compulsive, I just want to make sure I'm not running too lean, and potentially burning a hole in my piston. All signs, except for the lack of a chocolate brown plug electrode, suggest I have nothing to worry about. Just the same, I'm running the StarTron (which, my mechanic advises me, is much better than StaBil) out and will do another plug chop after a few fill-ups of 93 octane petrol.