― EGR control: It is difficult to recirculate exhaust gas because of the influence of the two-stage air charging pressure, therefore, the intake shutter valve is closed during EGR control to make recirculated exhaust gas induction easier.
― DPF regeneration control: Intake air is reduced during DPF regeneration control to cause the exhaust gas temperature to increase more easily.
― During deceleration: Intake air is reduced so that the catalyst temperature is not lowered by the incoming outside air.