To reduce load applied to an EGR valve by opening the EGR valve from a closed state according to pulsation of exhaust pressure or intake pressure applied to an EGR passage.
An EGR apparatus includes an EGR passage 17 and an EGR valve 18 provided in the EGR passage 17 to regulate an EGR flow rate in the EGR passage 17. The EGR valve 18 is of such a type that it opens by moving a valve element 33 from a closed state in which the valve element 33 is seated on a valve seat 32 to an upstream side in the EGR passage 17 against exhaust pressure or intake pressure of an engine 1. An electronic control unit (ECU) 50 for controlling the EGR valve 18 according to an operating state of the engine 1 starts to open the EGR valve 18 except timing when the exhaust pressure or the intake pressure of the engine 1 is at its peak in opening the EGR valve 18 from the closed state.
NOKAWA SHINICHIRO
IRISAWA YASUYUKI
HOKUTO HIROYUKI
TOYOTA MOTOR CORP
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