System Operation
General Motors Active Fuel Management engine control system has the ability, under certain light load driving conditions, to provide maximum fuel economy by deactivating 4 of the engines 8 cylinders. The engine will normally operate on 8 cylinders in V8 mode during starting, idling, and medium or heavy throttle conditions. When commanded ON, the engine control module (ECM) will direct the active fuel management system and deactivate cylinders 1 and 7 on the left bank and cylinders 4 and 6 on the right bank, forcing V4 mode. Refer to Lubrication Description (RPO LY2) or Lubrication Description (RPO LC9/LY5/LMG) or Lubrication Description (RPO LY6) or Lubrication Description (RPO L76) or Lubrication Description (RPO L92) and Cylinder Deactivation (Active Fuel Management) System Description .