Do I just walk into a Chev dealership and ask them to reprogram "the computer"?

A Chevrolet Dealership can "reflash" (aka reprogram) the vehicles ECU (electronic control unit) with a scan tool called the "Tech 2". The dealership will not likely do this without reason and they may ask you why you want it done. They may not do it without first diagnosing the problem that you are experiencing. This is the best method. Carefully explain your concern, and after a proper diagnosis, they may reflash or take another avenue toward the correct repair.