One or more heater & AC (HVAC) temperature and/or air delivery mode door actuator may fail, resulting in improper temperature or air delivery. If this occurs, fault code(s) should be stored in the HVAC control module which should assist in diagnoses.
2009 GMC Sierra 1500 Problem Reports
Most Reported 2009 GMC Sierra 1500 Problem Reports
The distributor may develop internal faults. This can cause a rough running engine or stalling condition, the Check Engine Light may or may not illuminate. Our technicians tell us that the distributor should be overhauled or replaced to correct this concern.
A Loose or worn gas cap may cause Check Engine Light to illuminate.