A control system of an internal combustion engine includes an S/V ratio changing mechanism able to change an S/V ratio of a combustion chamber and a detection device having an output value changing in accordance with a hydrogen concentration in exhaust gas, which increases along with an increase in the S/V ratio, the internal combustion engine being controlled by the output value of the detection device. Further, the output value of the detection device or a parameter relating to operation of the internal combustion engine is corrected in accordance with the S/V ratio of the above S/V ratio changing mechanism.

A variable valve lift (VVL) system for an internal combustion engine is provided that utilizes hydraulic fluid supply pressure feedback to provide noise free operation. The VVL system includes a high pressure pump, a solenoid valve, a pressure translating device, a one-way valve, and a hydraulic fluid pressure sensor. The high pressure pump is fluidly connected to the solenoid valve and pressure translating device by at least one fluid gallery that forms a high pressure chamber. The solenoid valve selectively fluidly connects the high pressure chamber to a middle pressure chamber formed by at least one fluid gallery that fluidly connects the one-way valve to the solenoid valve. The hydraulic fluid pressure sensor is arranged to detect a hydraulic fluid supply pressure of the one-way valve and provides feedback to an electronic controller that determines a proper fluid intake opening timing of the solenoid valve.

The control system of an internal combustion engine of the present invention comprises an S/V ratio changing mechanism able to change an S/V ratio of a combustion chamber and a detection device having an output value changing in accordance with a hydrogen concentration in exhaust gas, which increases along with an increase in the S/V ratio, the internal combustion engine being controlled by the output value of the detection device. Further, the output value of the detection device or a parameter relating to operation of the internal combustion engine is corrected in accordance with the S/V ratio of the above S/V ratio changing mechanism. Due to this, even if the hydrogen concentration in the exhaust gas increases along with an increase in the S/V ratio, the internal combustion engine can be suitably controlled.

A lift amount variable mechanism is configured to switch a cam for driving an intake valve (drive cam) between two types of intake cams in lift amount (i.e. a large lift cam and a small lift cam). In a first embodiment of this disclosure, the lift amount variable mechanism is controlled by an ECU so that the small lift cam is selected as the drive cam for control that promotes activation of an exhaust gas cleaning catalyst (catalyst warm-up control).

Aspects of the present invention relate to methods of stop/start of an internal combustion engine provided with a CVVL system; also a control unit and a vehicle for employing the methods.

Methods, devices, controllers, and algorithms are described for operating an internal combustion engine wherein at least some firing opportunities utilize low temperature gasoline combustion (LTGC). Other firing opportunities may be skipped or utilize some other type of combustion, such as spark ignition. The nature of any particular firing opportunity is dynamically determined during engine operation, often on a firing opportunity by firing opportunity basis. Firings that utilize LTGC produce little, if any, nitrous oxides in the exhaust stream and thus, in some implementations, may require no aftertreatment system to remove them from the exhaust stream.

Methods, devices, controllers, and algorithms are described for operating an internal combustion engine wherein at least some firing opportunities utilize low temperature gasoline combustion (LTGC). Other firing opportunities may be skipped or utilize some other type of combustion, such as spark ignition. The nature of any particular firing opportunity is dynamically determined during engine operation, often on a firing opportunity by firing opportunity basis. Firings that utilize LTGC produce little, if any, nitrous oxides in the exhaust stream and thus, in some implementations, may require no aftertreatment system to remove them from the exhaust stream.

A variable valve duration apparatus may include a first cam rotating with a camshaft; a second cam rotating with the camshaft; a first operation device that is operated by the first cam to generate a valve lift; a second operation device that is operated by the second cam to generate the valve lift; and a controller controlling the first operation device or the second operation device to generate the valve lift according to an operation state of an engine.

The present disclosure relates to internal combustion engines. The teachings thereof may be embodied in a method for determining a torque reserve for an internal combustion engine during a change of an operating state. The method may include: operating the internal combustion engine in the first operating state; determining a rotational speed; determining a torque; determining an air mass setpoint value based on the rotational speed and the torque in the second operating state; calculating a torque setpoint value depending on the rotational speed and the air mass setpoint value in the first operating state; and determining a torque reserve for the transition from the first operating state to the second operating state using based on the torque and on the torque setpoint value.

A method, an apparatus, a computer program, an engine intake system, and a vehicle are provided. The method is for controlling an air charge provided to a vehicular engine. The method comprises determining a target valve lift of an inlet valve in a continuously variable valve lift system based, at least in part, on: a required air charge for a given torque request; and an estimate of a variable pressure of an engine intake manifold for a time when the inlet valve is to be actuated in accordance with the target valve lift. The method also comprises controlling actuation of the inlet valve in the continuously variable valve lift system in accordance with the determined target valve lift.