Abstract: In a multi-stage fuel-injection internal combustion engine employing a fuel injection system and a variable valve actuation system, engine valve timings are variably controlled depending on engine operating conditions. An electronic engine control unit is configured to execute cooperative control of the timing of sub-injection, injected before main injection, responsively to intake valve closure timing, and also to execute cooperative control of the timing of sub-injection, injected after the-main injection, responsively to exhaust valve open timing.

Abstract: In a control apparatus for controlling a variable valve actuation system employed in an internal combustion engine, engine/vehicle sensors are provided to detect at least a cylinder pressure in an engine cylinder for monitoring a change of state in combustion, arising from fluctuations in states/characteristics of air-fuel mixture such as a change in fuel property. Also provided is a control system that controls the variable valve actuation system responsively to a manipulated variable modified based on the cylinder pressure reflecting the change of state in combustion by a model of combustion.

Abstract: In a variably operated valve system for a compression ignition engine, an adjustment mechanism is controlled by means of a control section to detach an intake valve closure timing from a bottom dead center in accordance with an engine driving condition, and an engine start securing section guarantees an engine start even at least one of cases during a failure in the control section, during a stop of the engine, and during a start of the engine.

Abstract: In a control apparatus for controlling a variable valve actuation system employed in an internal combustion engine, engine/vehicle sensors are provided to detect at least a cylinder pressure in an engine cylinder for monitoring a change of state in combustion, arising from fluctuations in states/characteristics of air-fuel mixture such as a change in fuel property. Also provided is a control system that controls the variable valve actuation system responsively to a manipulated variable modified based on the cylinder pressure reflecting the change of state in combustion by a model of combustion.

Abstract: In a multi-stage fuel-injection internal combustion engine employing a fuel injection system and a variable valve actuation system, engine valve timings are variably controlled depending on engine operating conditions. An electronic engine control unit is configured to execute cooperative control of the timing of sub-injection, injected before main injection, responsively to intake valve closure timing, and also to execute cooperative control of the timing of sub-injection, injected after the-main injection, responsively to exhaust valve open timing.

Abstract: In a compression ignition engine employing a variable valve actuation mechanism variably adjusting an intake valve characteristic including at least one of an intake valve lift and an intake valve closure timing, a control system operates to temporarily lower an effective compression ratio of the engine by controlling the intake valve characteristic during a cranking period of cold starting operation. At a point of time when a predetermined cranking speed threshold value has been reached owing to a cranking speed rise, the effective compression ratio is risen by controlling the intake valve characteristic. After combustion of the engine has been stabilized, the intake valve characteristic is brought closer to a desired value determined based on engine operating conditions by way of closed-loop control.

Abstract: In a variably operated valve system for a compression ignition engine, an adjustment mechanism is controlled by means of a control section to detach an intake valve closure timing from a bottom dead center in accordance with an engine driving condition, and an engine start securing section guarantees an engine start even at least one of cases during a failure in the control section, during a stop of the engine, and during a start of the engine.

Abstract: An idle speed control device has a valve portion disposed in an auxiliary intake air passage by-passing a throttle valve disposed in a main intake air passage for opening and closing a valve provided in the auxiliary air passage, and a spring urging the valve portion to close. The spring is arranged in a portion separated from the air flow in the auxiliary intake air passage, and the valve portion has a guide portion formed therein to be integrated therewith for guiding sliding of the valve portion.

Abstract: A turbocharger driven by exhaust gases of an internal combustion engine wherein a scroll is split into two sections extending side by side in parallel to the direction of flow of the exhaust gases. A control valve for controlling the inflow of exhaust gases into at least one of the two sections of the scroll is provided, and a valve seat structure cooperating with the control valve is formed separately from a turbine casing and secured in place between an inlet portion of the turbocharger and an exhaust passageway of the engine.