I have a 2007 cobalt supercharged 2.0 just brought it about a week ago. Just wondering when I try to start it, it crank sometimes itll backfire when it doesnt start but when it eventually do start it runs and drives fine. Any advice on where to start. Fuel pump comes on I emptied all the gas just incase it was dirty. Changed the filter as well. The codes in it was b1325 and that's it besides p2229. It was missing the baro sensor so I replaced it.