The sportage was nearing empty (ie. the light was on) so I pulled into the gas station and filled it. 15 seconds or so after I pulled out of the gas station in began to sputter and backfire but didn't stall. I have driven it about 50 miles like this and the condition has not improved. While driving the Check Engine light flashes. I pulled the codes when I made it home and there were "Low voltage to Bank 1 sensor 2" and "Misfire on Cylinder 3" I have had the first code for quite a while. Do you think it is just bad gas, or do you think there is a more serious problem? FYI, the gas tank is brand new (less than 2 months) and the pump and filter were replaced at the same time. Any thoughts?