So my wife and I are entering our 3rd month of owning a 2009 Saturn outlook awd. Check engine light came on today. Auto zone reader says "oxygen sensor circuit high voltage bank 1 sensor 1". They don't have any schematic or anything for it though. Can somebody point me in the right direction and to where this sensor is on the vehicle so I can swap it. I was kind of wondering why we were getting such horrible gas mileage too. I've been told most likely this was the reason.