Thanks for the info. It was the most helpful, informative and well written entry I've seen. (No offense guys) -What exactly does "open loop" mean? -When is it helpful to disconnect the power to reset the computer? -Is there any advantage to keeping the O2 sensor connected besides legality and emissions? My 6 seems to idle nicer without it, but less predictable performance. Does the O2 keep engine operating more consistently? -Apprecitate any other info. You're knowledge of the intricacies of the most mysterious workings of the 6 motor is most impressive.