One problem related to automatic transmission cooler has been reported for the 2005 Chevrolet Cobalt. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2005 Chevrolet Cobalt based on all problems reported for the 2005 Cobalt.
The first time it happened, was at interstate speeds. (60 to 70mph) the second, was in city stop and go traffic. The third was backing out of my driveway after a 5 minute idle. The fourth was when my last mechanic was test driving it because he thought he'd fixed it. Dash lights blink on and off, all warning lights come on, engine cooling fans stop operating, transmission hunts for what gear it should be in; resulting in the transmission self destructing. Engine management, other than the cooling fans, seems to be unaffected. I've replaced 4 tcm's so far; as all mechanics say that is the problem. It works for a few days or a week, then the same problem manifest. This seems to be a problem with quite a few gm vehicles.