At the start of the engine, when the temperature of the catalyst is less than the activation temperature, control for activating the catalyst (i.e., activation control) is performed. In the activation control, the first and second discharge actions of the ignition apparatuses are controlled. The first discharge action is performed to ignite the mixed gas in the cylinder. The second discharge action is performed to generate ozone. The first discharge action is performed immediately after the start of the cranking. The first discharge action is performed in the crank angle section at the retard side rather than the compression TDC. The first discharge action is performed in every cylinder. The second discharge action is performed before the start of the cranking. The second discharge action is performed in the other cylinder except for the initial combustion cylinder.

A controller for a hybrid vehicle restarts an engine in a start mode selected from multiple start modes. The multiple start modes include a first start mode of starting combustion in the engine when a clutch starts transmitting torque and a second start mode of starting combustion in the engine after the clutch starts transmitting torque. The controller is configured to, in a case in which the engine is restarted in the second start mode, measure a cranking start time from when engagement of the clutch is commanded to when transmission of the torque through the clutch is started, and only when measurement of the cranking start time has been completed after the vehicle is activated, restart the engine in the first start mode.

At the start of the engine, when the temperature of the catalyst is less than the activation temperature, control for activating the catalyst (i.e., activation control) is performed. In the activation control, the first and second discharge actions of the ignition apparatuses are controlled. The first discharge action is performed to ignite the mixed gas in the cylinder. The second discharge action is performed to generate ozone. The first discharge action is performed immediately after the start of the cranking. The first discharge action is performed in the crank angle section at the retard side rather than the compression TDC. The first discharge action is performed in every cylinder. The second discharge action is performed before the start of the cranking. The second discharge action is performed in the other cylinder except for the initial combustion cylinder.

A start control system for an engine is provided. The engine is a direct injection engine, and the engine is provided with a starter motor. The start control system includes an electronic control unit. The electronic control unit is configured to execute fuel injection and ignition in a cylinder in an expansion stroke so as to start the engine without using the starter motor, when the electronic control unit determines that a restart condition of the engine is satisfied immediately before the engine is stopped. The electronic control unit is configured to control an ignition delay time based on at least one of a rotational direction and a rotational speed of a crankshaft, during execution of the fuel injection. The ignition delay time is a period of time from fuel injection into the cylinder in the expansion stroke to ignition.

In the cases where a reverse operation of a crankshaft is performed after fuel injection and ignition in a cylinder in a power stroke and it is determined that an engine start is failed, a starter motor is operated, and fuel injection and ignition are executed in the cylinder in the compression stroke to start an engine.

A control device of a vehicle including an engine, an electric motor, and a clutch disposed on a power transmission path between the engine and the electric motor, the control device of a vehicle performing an ignition start causing combustion in a cylinder of the engine to rotate the engine at a start of the engine, the control device of a vehicle switching a cylinder in which combustion is first caused in the engine based on an actuation during a rotation stop process of the engine of an exhaust valve in a cylinder stopped in an expansion stroke, when performing the ignition start at the start of the engine.

In the cases where a reverse operation of a crankshaft is performed after fuel injection and ignition in a cylinder in a power stroke and it is determined that an engine start is failed, a starter motor is operated, and fuel injection and ignition are executed in the cylinder in the compression stroke to start an engine.

A start control system for an engine is provided. The engine is a direct injection engine, and the engine is provided with a starter motor. The start control system includes an electronic control unit. The electronic control unit is configured to execute fuel injection and ignition in a cylinder in an expansion stroke so as to start the engine without using the starter motor, when the electronic control unit determines that a restart condition of the engine is satisfied immediately before the engine is stopped. The electronic control unit is configured to control an ignition delay time based on at least one of a rotational direction and a rotational speed of a crankshaft, during execution of the fuel injection. The ignition delay time is a period of time from fuel injection into the cylinder in the expansion stroke to ignition.

A control unit according to the present invention performs an automatic stop control in which an injection of fuel from a fuel injection valve is stopped to stop a rotation of an engine when an automatic stop condition is satisfied. Furthermore, the control unit performs a first injection, in which fuel is injected from the fuel injection valve of a cylinder in an expansion stroke, and an ignition operation for igniting the fuel injected by the first injection, when a restart demand occurs after an initiation of the automatic stop control. In addition, the control unit performs a second injection, in which fuel is injected from the fuel injection valve of a cylinder in a compression stroke, and an ignition operation for igniting the fuel injected by the second injection. Then, the control unit performs a third injection, in which fuel is injected from the fuel injection valve of a cylinder in a compression stroke, when it judges that a start-up failure for which a crank angle of the cylinder which is in the compression stroke after the second injection cannot get over the compression top dead center occurs or will occur.

In an automatically stopped internal combustion engine, a rotation speed at next and subsequent ignition timings is predicted at every ignition timing of the internal combustion engine after the internal combustion engine is stopped automatically. Whether self-restorable restarting is allowed is determined according to a comparison result of the predictive rotation speed and a self-restoration determination rotation speed, so that self-restorable restarting is performed in a reliable manner.