Engine control device, vehicle, engine control program, and engine control method

An engine control program causing a computer that controls an engine to perform:

• compression release control of stopping fuel injection from an injector in a selected cylinder and increasing an amount of fuel injection in a non-selected cylinder different from the selected cylinder, in a case where a catalyst temperature of a catalyst for purifying exhaust gas of the engine is lower than a first threshold temperature, the selected cylinder being one or some of a plurality of cylinders included in the engine;
• and
• Miller cycle control of operating an intake valve such that an amount of intake air is reduced in all of the plurality of cylinders as compared with the case where the catalyst temperature is lower than the first threshold temperature, and reducing the amount of fuel injection, in a case where the catalyst temperature is equal to or higher than the first threshold temperature.

An engine control method for controlling an engine, the engine control method comprising:

• performing compression release control of stopping fuel injection from an injector in a selected cylinder and increasing an amount of fuel injection in a non-selected cylinder different from the selected cylinder, in a case where a catalyst temperature of a catalyst for purifying exhaust gas of the engine is lower than a first threshold temperature, the selected cylinder being one or some of a plurality of cylinders included in the engine;
• and
• performing Miller cycle control of operating an intake valve such that an amount of intake air is reduced in all of the plurality of cylinders as compared with the case where the catalyst temperature is lower than the first threshold temperature, and reducing the amount of fuel injection, in a case where the catalyst temperature is equal to or higher than the first threshold temperature.