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Discussion Starter #1 (Edited)
So I am new to the whole Cobalt world as I just purchased a 2007 Cobalt. It has just over 11,000 miles on it and an automatic transmission. I have one question, and hopefully I will make sense. Say I am driving down the road in the final drive gear and I give the car a little gas (enough to make the car drop a gear for passing but not flooring it) the RPM's start jumping up about 500 RPM's and back down until I give it a little more gas does it finally downshift. It's as if the car wants to downshift but hasn't decided that's what it wants to do. Like I said hopefully this makes since. I am going to bring the car to dealership soon but I just wanted to see if someone here knew what this was all about before I head there. Thank you.
 

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What MPH are you at when you do this?

When you have the selector in "D" the ECM and TCM are working to keep the MPG as high as possible. Until you really push the gas pedal, the tranny wants to stay in the highest gear to keep emissions low and MPG high.
 

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If you do a search for my posts you'll find I had the same problem with a NEW LS COBALT07'. They had the car for an entire day and even drove other Cobalts and told me there were no codes, the trans was shifting fine and not giving any faulty conditions on there scanner. They did notice the odd up/down shift when in OD and giving it just barely any gas. They said their other "NEW" Cobalts did the same thing. My problem went away on it's own. But I did have the same problem you are experiencing. Hopefully if you take it in they will find the problem ... mine went away eventually. Not sure what was wrong with it as the dealer could not find a problem with the trans on there scanner but they did feel the "shudder" between OD and D and the RPM change.
 

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The Cobalt transmission is still fairly primitive by today's standards. If you don't give it enough gas then it will bog and delay slightly. As far as the ECM is concerned, that slight pressure of the pedal could just be you trying to maintain speed over a hill or accelerating 40-45mph, and no reason to drop a gear. Hope that helps.
 

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Discussion Starter #5
Thanks to all who responded so quickly. Everyone's answers helped me out quit a bit, so thanks again. It all makes since about the ecm w/ the whole drive by wire. This is something new to me for sure. I kind of thought that it had something to do with the computer and throttle, I mean we are not talking about a corvette here so I am sure they didn't work ALL of the bugs out of the computer. I am going to still take it to the dealership and see if they can come up with something but I just wanted to get some opinions before I get there. Thanks a million!
 
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