Diagnosing cobalt 2010

car is running way hotter than normal, also sluggish, shifting rough, ac has been a little less cold and a whining noise when accelerating. Any ideas 20500 miles

Could be several things.

Dying water pump comes to mind…

A couple of questions… 1) Should there be an extra zero on that mileage? 20,000 miles on a 12 year old car is really low. And 2) Is the check engine light on?

If it is on, get the codes read for free at an auto parts store and post the actual codes, P1234 like that, here. Don’t say what the parts person told you they mean, the actual codes. Also let us know if you will attempt to fix it or a professional. Post back and we’ll try and help

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In any event, with a 12 year old vehicle with–probably–more than 200k miles, there are a lot of possibilities, including multiple sources for the varied symptoms.

I would be very surprised if it wasn’t lit-up. Hopefully the CEL isn’t flashing/blinking.

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If your engine is actually overheating here, keep in mind that it doesn’t take many repeated episodes to cause expensive engine damage.

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When engine seems to be overheating, pop hood. Are the engine compartment fans spinning? If not, that’s probably the problem. CT puzzler, recent, was about a mistake installing radiator fans so they turned the wrong direction, causing overheating. So if there’s been any work on the radiators, and the fans are spinning, make sure they are blowing the air toward the engine, not away.