This forum seems to be dying a slow drawn out death. In an effort to regain some interest, I am asking what kind of mileage are you getting with your Cobalt ? Here is a picture of my fuel economy gauge, this isn’t a fluke, the mileage is repeatable. It is approx. 6 miles of city stop signal to stop signal in traffic then highway morning early rush traffic for about 23 miles. I use the cruise control set at about 63 MPH on two different highways on low rising & down grades heading up to just the start of the foothills West of Denver. This is on a 2007 Cobalt LT Coupe, auto trans., and it is a year too old to be a XFE Cobalt, that didn’t come out until 2008.