Control device for internal combustion engine and control method for internal combustion engine

A control method for an internal combustion engine including an engine body, a fuel injection valve configured to inject fuel into a combustion chamber of the engine body, and a vibration sensor configured to detect vibration of the engine body, the control method comprising:

• setting, by an electronic control unit, a target injection amount and a target injection timing based on an engine operation state;
• controlling, by the electronic control unit, an injection amount and an injection timing of fuel to be injected from the fuel injection valve to the target injection amount and the target injection timing, respectively;
• detecting, by the electronic control unit, an ignition timing of fuel based on a vibration component of the engine body in a specific frequency bandwidth, the specific frequency bandwidth being a bandwidth on a low frequency side of a frequency bandwidth where the engine body undergoes elastic vibration, and the specific frequency bandwidth being a bandwidth where a ratio of a combustion vibration component that is generated when the engine body is subjected to combustion pressure to vibration components detected by the vibration sensor becomes equal to or greater than a predetermined value;
• and correcting, by the electronic control unit, at least one of the target injection amount and the target injection timing based on a deviation between the detected ignition timing and a target ignition timing according to the engine operation state, wherein the specific frequency bandwidth is a frequency bandwidth of 0.1 kHz to 1.8 kHz.