Is there a waranty fix with what seem to be electronic issues with my 2010 Chevy Traverse?

The check engine light has been on for two years in my Traverse and my local mechanic doesn't know why. for about the same amount of time, when filling the tank we have to turn all electronics off and then after the fill we have to pump the gas pedal and coax it into starting. Again, local mechanic doesn't know what to do that won't cost a fortune, so advised to continue driving if what we do works. For the last month or so the stabilitrak warning light has come on periodically and then the reduced engine power light also comes on. This happens when it is really cold. At first nothing else happened, but the last three times we did lose power. I went down to 40mph while driving on the interstate and then at 21 below last night we couldn't go over 10-15 mph. After turning the car off for a while it normally re-sets which it did last night and we finally made it home. I am taking the advice of a previous forum member and will call chevy tomorrow for a file number and then GM to complain. I also need to get from them the name of an auto repair shop in our small area that can get to the bottom of these issues directly without trying numerous things first that will cost me an arm and a leg.