traction control off reduced engine power

Check engine, Service stability track and traction control light are all on . And when its warm out the Acadia will have reduce engine power and will shut off at any speed or just sitting idle. If u let it sit for a few min it will fire right back up and go.. Replaced the battery and all coil...

2012 GMC has been in the dealership shop (3) times for the above. The check engine light will go on with the message Service Stabiltrak, then Service Traction Control, Then Traction Control Off, then Reduced Engine Power. Always an electrical smell in cab of car. Last time was in shop they...