Severe Commercial Use Vehicles Only: Lubricate chassis components every 5 000 km/3,000mi.Have underbody flushing service performed. See "Underbody Maintenance" inExterior Care.
Power Mode Description and Operation
GMLAN and Media Oriented Systems Transport (MOST) Wiring RepairsSpark Plug Inspection Engine Control
Spark Plug UsageEnsure that the correct spark plug is installed. An incorrect spark plug causes driveabilityconditions. Refer to the Electronic Parts Catalog.Spark Plug InspectionInspect the terminal post (1) for damage.Inspect for a bent or broken terminal post-(1).Test for a loose terminal post (1 ...