I recently changed an oxygen sensor because I was getting a p1148 code. Upstream passenger side. I pulled the battery for 5 minutes to clear the code. Now after 50 miles I'm getting p1279 which says a/f sensor 1......is this a different sensor or just some generic code? I had one of my companies fleet mechanics say to go to AutoZone and have them clear the code before purchasing any parts or chasing this. He said sometimes the battery pull doesn't clear everything. My vehicle is complete stock.