An ECU executes (300) a program including a step (S202) of opening an electromagnetic ASV (232) while a vacuum pressure ASV (1) and a vacuum pressure ASV (2) are controlled so as to be closed, and an air pump (200) is controlled so as to be stopped in a case where an air amount GA that is an amount of air introduced into an engine (100) is equal to or larger than a predetermined air amount GA (0), and a coolant temperature TW at the starting time of the engine is equal to or higher than a predetermined coolant temperature TW (0) (“YES” in step S200); a step (S204) of detecting a pressure; a step (S206) of closing the electromagnetic ASV; and a step (S402) of determining that failure has occurred in at least one of the vacuum pressure ASV (1) and the vacuum pressure ASV (2), that is, one of the vacuum pressure ASV (1) and the vacuum pressure ASV (2) remains in an opened state and cannot be closed when there is a pulsation of the pressure that is detected while the electromagnetic ASV is opened (“YES” in step S400).