(6) Amount of Injection Quantity Intake Pressure Correction a. Limits the maximum injection quantity in accordance with the intake pressure, in order to minimize the discharge of smoke when the intake air pressure is low. Amount of Intake Air Pressure Correction Q000133E Engine Speed (7) Amount of Injection Quantity by Atmospheric Air Pressure Correction a. With using atmospheric air pressure sensor signal, the maximum injection quantity curve is corrected as shown in the right figure. Amount of Atmospheric Air Pressure Correction Q000134E Engine Speed (8) Idle Speed Control System (ISC) a.
Controls the idle speed by regulating the injection quantity in order to match the target speed, which has been calculated by the computer, with the actual speed. The functions of the ISC can be broadly divided into the following two items: • Auto ISC Controls the idle speed in accordance with the water temperature. Target Speed Water Temperature Q000135E • Manual ISC Controls the idle speed in accordance with the idle speed indicated on the manual idle setting 33