•  If there is a difference between the target idle speed and the actual idle speed, the PCM controls the fuel injection amount so that the actual idle speed corresponds to the target idle speed.

•  Controls engine speed based on the input signal from the engine coolant temperature sensor (–30—10 °C {–22—50 °F}) so that the engine speed while warming up corresponds to the target engine speed.

•  Calculates the particulate matter amount based on the input signal from the exhaust gas pressure sensor and control engine speed so that it corresponds to the target engine speed during diesel particulate filter manual regeneration.

•  If there is abnormal combustion of soot during diesel particulate filter manual regeneration, the exhaust gas temperature increases which may cause damage to the diesel particulate filter. At this time, post injection is stopped and the engine speed increases to 2,500 rpm. Due to this, the diesel particulate filter is cooled by sending low temperature exhaust gas with high speed to the oxidation catalytic converter, preventing damage.

•  The PCM detects the engine speed fluctuation while idling and corrects the fuel injection amount per each cylinder. Due to this, the variance in fuel injection amount caused by ununiformity of the cylinders (such as fuel injectors) and engine vibration while idling are reduced.