New to the stang world, trying to learn this new to me beast...bought 3 weeks ago and today I got cel p0420..which usual is a cat but I'm hoping in for a little insight on my o2 sensors...gonna test them but before I get to it had a question for u guys...bought the car w duel side exhaust which u can smell running all rich...not sure due to exiting body right behind door but can smell at lights...also has a SCT xcal tuner tuned w what I believe arenpreset tunes for 87\91octane...set on 87 as of now I believe...but can running rich foul out o2 sensors and can they b cleaned and reused or just replaced...I believe they are all OEM and car has 150k....how do they cats hold out o these beast typically...