Abnormality detection apparatus for an exhaust gas recircultation apparatus

An apparatus for detecting abnormality of an EGR apparatus. An ECU 42 feedback controls the opening degree of an EGR valve 34 such that an actual intake air amount matches a target intake air amount that corresponds to the running state of an engine 11. When a feedback term of the feedback control is outside a relatively widely range, the ECU 42 alters the opening degree of a throttle valve 24 in order to check for an abnormality in an EGR apparatus 32. If the amount of change of the feedback term is less than or equal to a predetermined value after the alteration of the opening degree of the throttle valve 24, the ECU 42 determines that the EGR apparatus 32 is abnormal.