CONTROLLER AND CONTROL METHOD FOR INTERNAL COMBUSTION ENGINE

A controller for an internal combustion engine is configured to execute: a pressure calculation process that calculates pressure of gas in a crank chamber based on a running state of the internal combustion engine; a first injection process that causes a water injection valve to inject a first injection amount of water when an intake valve is open; and a second injection process that causes the water injection valve to inject a second injection amount of water when the intake valve is closed. The controller is further configured to set a ratio of the first injection amount to a sum of the first injection amount and the second injection amount to a smaller value when the pressure is greater than or equal to a specified value than when the pressure is less than the specified value.