My 4.6 is throwin' a bad O2 code on the left side (Sorry, my "mechanic" unplugged and shutdown his scanner B4 I could see the damn numbers, figures). It'll clear itself then comeback. I'm in CA so I gotta attend to it or "The Terminator" won't let me drive anymore. I'm thinkin' I need to put my DMM on the front sensor to get the voltage from it when hot. Any and all embellishments concerning O2 testing and if they throw an intermittant CK. ENG. lite while dying would be appreciated.