[Ed Wright]

Also, all Wideband sensors don't read the same. Learned that on my dyno. I bought a new one, and found it showed leaner air/fuel numbers than the old one. I ordered yet another, put my pickup on the dyno, and made 2 pulls, plugged in the new one, A/F went from 13.0-1 to 13.25-1. Put the old sensor back in, 13.0-1. Ordered yet another new sensor. Back to 13.0-1. Tagged the Lean sensor at ".25 Lean", and kept it for a spare. If I had a car in that was not as rich as I expected, I put the spare in to verify the sensor I was using was not indicating a false lean condition. Leaded fuel does degrade O2 sensors. I always keep a known good spare for my FAST system on my race car. If you buy a spare, I would back-to-back test them to verify they agree. That is why you cannot just tell a guy to tune his car for a given magic number A/F ratio. His sensor may not read just like yours. That's why we test, right? Mine does not make the best power at the same air/fuel ratio with all fuels, either.
Always something, right?