Abstract: A controller configured to control a hybrid vehicle includes a catalyst temperature increase control unit configured to execute a catalyst temperature increase control of increasing a temperature of a three-way catalyst device, a motoring control of rotating a crankshaft of an internal combustion engine with power of a motor in a state in which combustion of the internal combustion engine is stopped, and a fuel introduction process of introducing unburned air-fuel mixture into an exhaust passage by performing fuel injection in the internal combustion engine during the execution of the motoring control.

Abstract: A controller for an internal combustion engine includes a fuel introduction process of introducing an air-fuel mixture containing fuel injected by a fuel injection valve into an exhaust passage without burning the air-fuel mixture in a cylinder. The fuel introduction processor is configured to perform, during the execution of the fuel introduction process, a determination process of determining whether afterfire, in which the air-fuel mixture burns at an upstream side of a three-way catalyst device in the exhaust passage, has occurred and a stopping process of stopping the fuel introduction process when determining in the determination process that the afterfire has occurred.

Abstract: When stopping combustion in a cylinder under a situation in which the crankshaft of an internal combustion engine having an ignition device is rotating, a controller executes a fuel introduction process of injecting fuel from a fuel injection valve and introducing the fuel from inside the cylinder to the exhaust passage without burning the fuel. Also, the controller executes a storing process before starting the fuel introduction process. In the storing process, the controller stores oxygen in a three-way catalyst by executing a fuel cutoff process of stopping fuel injection of the fuel injection valve under a situation in which the crankshaft is rotating.

Abstract: When stopping combustion in a cylinder under a situation in which the crankshaft of an internal combustion engine having an ignition device is rotating, a controller executes a fuel introduction process of injecting fuel from a fuel injection valve and introducing the fuel from inside the cylinder to the exhaust passage without burning the fuel. Also, the controller executes a storing process before starting the fuel introduction process. In the storing process, the controller stores oxygen in a three-way catalyst by executing a fuel cutoff process of stopping fuel injection of the fuel injection valve under a situation in which the crankshaft is rotating.

Abstract: A controller configured to control a hybrid vehicle includes a catalyst temperature increase control unit configured to execute a catalyst temperature increase control of increasing a temperature of a three-way catalyst device, a motoring control of rotating a crankshaft of an internal combustion engine with power of a motor in a state in which combustion of the internal combustion engine is stopped, and a fuel introduction process of introducing unburned air-fuel mixture into an exhaust passage by performing fuel injection in the internal combustion engine during the execution of the motoring control.

Abstract: A controller for an internal combustion engine includes a fuel introduction process of introducing an air-fuel mixture containing fuel injected by a fuel injection valve into an exhaust passage without burning the air-fuel mixture in a cylinder. The fuel introduction processor is configured to perform, during the execution of the fuel introduction process, a determination process of determining whether afterfire, in which the air-fuel mixture burns at an upstream side of a three-way catalyst device in the exhaust passage, has occurred and a stopping process of stopping the fuel introduction process when determining in the determination process that the afterfire has occurred.

Abstract: A misfire determination device for an internal combustion engine includes an electronic control unit configured to determine whether execution of temperature rise processing in which a temperature of a catalyst is raised by an air-fuel ratio of one of the cylinders being controlled to be a rich air-fuel ratio lower than a stoichiometric air-fuel ratio and an air-fuel ratio of each of the other cylinders being controlled to be a lean air-fuel ratio higher than the stoichiometric air-fuel ratio is ongoing, determine occurrence of misfire based on whether a rotation variation amount of the internal combustion engine during non-execution of the temperature rise processing exceeds a first misfire determination value, and determine occurrence of misfire based on whether the rotation variation amount during the execution of the temperature rise processing exceeds a second misfire determination value exceeding the first misfire determination value.