reading through the book and seeing about testing o2 sensors and fuel trims for o2 sensors but nothing about sensors like 2012 nisan rouge where voltages stay around 2.5 volts and do snot switch much. am i missing something?
You are not. When the book was written, wideband AFR sensors were not so widely used as they are today.
Toyota and Honda has been using them since the early 2000's, but most everything on the road had traditional Zirconia o2 sensors.
Tyler was kind enough to pin some testing methods for wideband sensors from various manufacturers at the top of the Diagnostic Tools & Techniques section of the forum
