My car has been hesitating for a month I checked the plugs coil packs everything pretty much. I googled it and came across a post on here so I'll let you know how simple the problem was. On your a/c line there is a wiring harness. I pulled it to expose the side of the harness that was against the a/c line and wow there was the exposed wire I taped it off and drove it and the problem was solved. 2005 cobalt ss stock. My mechanic couldn't figure out but this forum did thanks.

 

Theres a extremely old tsb on that one,probably dated 2005 !!!!!!

 

Yeah that is a tricky one to TS but I'm guessing it was the AC pressure. Switch. Right? Those will. Give driveability problems. Curious, was there also a lean or rich code w ur P0301?

 

Yea it's an old post but my car only has 60000 so it helped alot. Not sure what codes they were I can ask my mech