Abstract: A vehicle includes an engine, a catalyst, an oxygen concentration detector, and a control device. The catalyst is configured to clean gas emitted from the engine. The oxygen concentration detector is configured to measure oxygen concentration in the catalyst. The control device includes at least one processor and at least one memory coupled to the at least one processor. The at least one processor is configured to perform processing including determining, based on condition of the engine and the oxygen concentration measured by the oxygen concentration detector, whether to prohibit the engine from being stopped.

Abstract: A vehicle includes an engine, a catalyst, an oxygen concentration detector, and a control device. The catalyst is configured to clean gas emitted from the engine. The oxygen concentration detector is configured to measure oxygen concentration in the catalyst. The control device includes at least one processor and at least one memory coupled to the at least one processor. The at least one processor is configured to perform processing including determining, based on condition of the engine and the oxygen concentration measured by the oxygen concentration detector, whether to prohibit the engine from being stopped.

Abstract: A vehicle includes an engine and an engine start controller. The engine start controller is configured to derive an integrated value while a target driving force derived on a basis of an accelerator operation amount is larger than or equal to a predetermined first threshold value from a time point when the target driving force becomes larger than or equal to the first threshold value, and to start the engine when the integrated value becomes larger than or equal to a predetermined second threshold value. The integrated value is obtained by integrating a difference value between the target driving force and the first threshold value.

Abstract: A vehicle includes an engine and an engine start controller. The engine start controller is configured to derive an integrated value while a target driving force derived on a basis of an accelerator operation amount is larger than or equal to a predetermined first threshold value from a time point when the target driving force becomes larger than or equal to the first threshold value, and to start the engine when the integrated value becomes larger than or equal to a predetermined second threshold value. The integrated value is obtained by integrating a difference value between the target driving force and the first threshold value.