EXHAUST GAS REFLUX DEIVCE FOR ENGINE

摘要

PROBLEM TO BE SOLVED: To reliably ensure the increase of an EGR gas amount when the opening of an intake throttle valve situated in an intake passage for the increase of an EGR gas amount is decreased when feedback control of an EGR gas amount is carried out such that an actual air amount is adjusted to a target air amount. SOLUTION: Feedback control of an opening degree of an EGR valve 24 is performed such that an actual air amount detected by an airflow meter 14 is adjusted to a target air amount. When EGR of large quantities is effected, an intake passage 12 is throttled by an intake throttle valve 18 disposed in the intake passage 12 in a spot situated right upper stream from an EGR gas introduction port 23b. When the opening degree of the intake throttle valve 18 is decreased and a maximum value of a securable actual air amount is decreased, the target air amount is varied to a low value and a state that an actual air amount reaches the target air amount through feedback control is secured.