Knock determination device for internal combustion engine

摘要

An engine ECU includes: an A/D (Analog/Digital) converter converting an analog signal transmitted from a knock sensor provided at a cylinder block into a digital signal; a bandpass filter passing only a vibration of a third order tangential resonance mode frequency band; and a bandpass filter passing only a vibration of a fourth order tangential resonance mode frequency band. The engine ECU determines whether the engine knocks, as based on the vibration selected by means of the bandpass filter or bandpass filter.