In order to compensate for tolerances in the fuel injection system, particularly those of the injectors, a characteristic map with specific values for each engine is stored in the DDE control unit at the end of the assembly line. The injection volume calculated by the DDE control unit during engine operation is varied slightly by these values thus improving the exhaust emission characteristics.
The harmonization values must be set to neutral if more than two injectors are replaced on the M57 or more than three injectors on the M67.
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