because of the high cost of SE-R O2 sensors I have decided to go to a Junkyard and bust a mission and find one and take it and pocket it ofcourse, well my question is how can you tell if its good?? Any info would help thankyou:) ===== 1992 Sentra SE-R with K&N Intake and 5ZIGEN exhaust (mandrel bent) Only injectors, oil line, guages, reprogram ECU, and a Downpipe away from boosting a T25 off a BB DET.