First time in years I can finally say... my S4 is error code free! Fixed a recent misfire and replaces the bank 2 sensor 2 O2 sensor. My Evap Purge Valve was acting up, but I put some Seafoam solution in it and to my surprise that cleared up that code. Let's see how long this last....
Ok well that didn't last long... just got a new code for the Bank 2 sensor 1 O2 sensor. I knew I should have replaced both. Oh well I was just trying to get past emissions at the time so another fix for another time.