Abstract: A port injection valve injects fuel to an intake passage. In multiple injection processing, a demanded injection quantity of the fuel is divided into a synchronous injection quantity and a non-synchronous injection quantity in accordance with at least one of: the load, which is a physical quantity having a correlation with the amount of air to be filled; and the temperature of an internal-combustion engine. The fuel is injected through intake non-synchronous injection and intake synchronous injection in this order. In the intake synchronous injection, the fuel is injected synchronously with a valve-open period of an intake valve. In the intake non-synchronous injection, the fuel is injected at a timing more advanced than in the intake synchronous injection.

Abstract: Provided are an internal combustion engine control device and control method in which a multi-injection process comprises performing an intake synchronized injection and an intake asynchronous injection to inject a required injection amount of fuel by operating a port injection valve for injecting fuel into an intake passageway. A variable process includes variably setting an injection timing for the intake synchronized injection on the basis of at least two of three parameters. The injection timing for the intake synchronized injection is expressed by the rotation angle of a crank shaft of an internal combustion engine. The three parameters include a rotational speed of the crank shaft of the internal combustion engine, a valve-opening start timing of an intake valve, and a temperature of an intake system of the internal combustion engine.

Abstract: A controller for an internal combustion engine includes processing circuitry. The processing circuitry executes a selecting process that selects one of a multi-injection process or a single injection process. The multi-injection process includes executing an intake synchronous injection and an intake asynchronous injection. The single injection process includes executing the intake asynchronous injection. In the intake synchronous injection, the fuel is injected in synchronization with a period in which an intake valve is open. In the intake asynchronous injection, the fuel is injected at timing advanced from timing of executing the intake synchronous injection. The processing circuitry changes ignition timing to a retarded side value in accordance with switching from execution of the multi-injection process to execution of the single injection process.

Abstract: A port injection valve injects fuel into an intake passage. A controller increases a base injection amount over a predetermined period after the internal combustion engine is started and gradually decreases an increase correction ratio of the base injection amount. One of two processes, a multiple injection process and a single injection process, is selected in order to inject the increased base injection amount of fuel. The increase correction ratio is set to be a smaller value in the multiple injection process than in the single injection process.

Abstract: Provided are an internal combustion engine control device and control method in which a multi-injection process comprises performing an intake synchronized injection and an intake asynchronous injection to inject a required injection amount of fuel by operating a port injection valve for injecting fuel into an intake passageway. A variable process includes variably setting an injection timing for the intake synchronized injection on the basis of at least two of three parameters. The injection timing for the intake synchronized injection is expressed by the rotation angle of a crank shaft of an internal combustion engine. The three parameters include a rotational speed of the crank shaft of the internal combustion engine, a valve-opening start timing of an intake valve, and a temperature of an intake system of the internal combustion engine.

Abstract: A port injection valve injects fuel to an intake passage. In multiple injection processing, a demanded injection quantity of the fuel is divided into a synchronous injection quantity and a non-synchronous injection quantity in accordance with at least one of: the load, which is a physical quantity having a correlation with the amount of air to be filled; and the temperature of an internal-combustion engine. The fuel is injected through intake non-synchronous injection and intake synchronous injection in this order. In the intake synchronous injection, the fuel is injected synchronously with a valve-open period of an intake valve. In the intake non-synchronous injection, the fuel is injected at a timing more advanced than in the intake synchronous injection.

Abstract: A controller for an internal combustion engine includes processing circuitry. The processing circuitry executes a selecting process that selects one of a multi-injection process or a single injection process. The multi-injection process includes executing an intake synchronous injection and an intake asynchronous injection. The single injection process includes executing the intake asynchronous injection. In the intake synchronous injection, the fuel is injected in synchronization with a period in which an intake valve is open. In the intake asynchronous injection, the fuel is injected at timing advanced from timing of executing the intake synchronous injection. The processing circuitry changes ignition timing to a retarded side value in accordance with switching from execution of the multi-injection process to execution of the single injection process.

Abstract: A port injection valve injects fuel into an intake passage. A controller increases a base injection amount over a predetermined period after the internal combustion engine is started and gradually decreases an increase correction ratio of the base injection amount. One of two processes, a multiple injection process and a single injection process, is selected in order to inject the increased base injection amount of fuel. The increase correction ratio is set to be a smaller value in the multiple injection process than in the single injection process.