Infernal combustion question

David, I would suggest you get a list of the TSB's for that car (apparently it's an actual 2005 model, although you may have bought it in 2004). This will cost you a nominal fee to see all of the TSB's, but they may shed some light on the subject at hand. Do a google search for Chevrolet Cobalt TSB.

You can't 'idiot proof' anything....every time you try, they just make
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