RPM Tachometer fluctuation/bouncing/jumping/pulsating while driving on side roads

[switchbacker]

RPM Fluctuation/bouncing while driving on side roads
I'm looking to clear the adapts on my 2008 Chevy Cobalt LT 2.2l Auto
RPM Fluctuation/bouncing while driving on side roads.
Once your going full blast on the Highway it doesn't happen. Only on the side roads.
the tach needle goes up and down about a hundred or two rpm's It's more annoying than a real
mechanical problem. I have read about relearn. I'm not sure how to proceed.
Thanks for any replies!
Switchbacker:|

 

[David S]

RPM Fluctuation/bouncing while driving on side roads
I'm looking to clear the adapts on my 2008 Chevy Cobalt LT 2.2l Auto
RPM Fluctuation/bouncing while driving on side roads.
Once your going full blast on the Highway it doesn't happen. Only on the side roads.
the tach needle goes up and down about a hundred or two rpm's It's more annoying than a real
mechanical problem. I have read about relearn. I'm not sure how to proceed.
Thanks for any replies!
Switchbacker:|

Relearn is a lie. Had this happen to my 2007 Cobalt, 2.2 LS.

Best thing for this one is to check the wires on the electrical, that's the problem... nothing mechanical. Clean them, switch them out, check fuses whatever you gotta do.

This happened to me several time over 12 months. Then it finally started to stall out, because it happened in intersections.

 

[roosterk0031]

Do you have anything plugged into ODB port, my scangauge cable is slightly damaged and if I bends just right make everything go wacky.

On my 2010 impala some wire were chaffed under the passenger seat and would make the car not start and all the gauges would go blank while driving when somebody was sitting in the seat, that one took a while to figure out. It only happened when I drove because it was wife car and never had anyone sitting there or kids were light enough it didn't affect it.