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Technical Description: Compensation: Knocking

Fig 1: Identifying Basic Fuel Quantity - Knocking
G03708755Courtesy of SAAB-SCANIA OF AMERICA, INC.

If the engine is knocking, it is corrected by retarding the ignition for the cylinder in question. If knocking persists despite the retardation, the correction factor will be increased. Closed loop will then be deactivated (if it was active) as it would otherwise counter-compensate.

Fig 2: Identifying Basic Fuel Quantity Graph - Knocking
G03708756Courtesy of SAAB-SCANIA OF AMERICA, INC.