To keep fuel systems clean, TOP TIER detergent gasoline is recommended. See Fuel (Gasoline).
If TOP TIER detergent gasoline is not available, one bottle of GM Fuel System Treatment Cleaner added to the fuel tank at every engine oil change, can help. GM Fuel System Treatment Cleaner is the only gasoline additive recommended by General Motors. It is available at your dealer.
#13-00-89-003: Vehicle Software Enhancements - (Mar 27, 2013)
Subject:Vehicle Software EnhancementsModels: 2014 and Prior GM Passenger Cars and Light Duty Trucks The new technology systems on today’s vehicles may have software enhancements availableto add additional functionality after the vehicle is produced. To meet customer expectations,GM may make th ...