Common rail injection Combustion Injection quantity correction Zero quantity calibration Injection quantity correction consists of two proce dures: The friction produced during opening and closing of the piezo injectors causes wear on the nozzle seat of the nozzle needle. This causes a change in the injec tion quantity over the service live of the injector. Main injection quantity correction Zero quantity calibration This change in the injection quantity can be corrected by adjusting the actuation duration (zero quantity cali bration). On engines with the Delphi injection system, correction is performed with the help of two knock sensors.
Main injection quantity correction With main injection quantity correction, the injected fuel quantity is corrected using the oxygen sensor upstream of the catalytic converter. The injection quantity is changed until the specified lambda value stored in the CDI control unit is reached. CDI injection system 1 Fuel heating element 2 Fuel filter housing 3 Rail 4 Rail pressure sensor 5 Pressure line 6 Piezo injector 7 High-pressure pump 8 Quantity control valve 9 Pressure regulator valve 23 Introduction of New Generation of 4-Cylinder Inline Engines, OM 651 q – This printout will not be recorded by the update service. Status: 09 / 2008 –