An internal combustion engine is provided including a cylinder including a piston connected to a rotatable crankshaft, an exhaust guide being arranged to guide a gas flow from the cylinder, an adjustable flow restriction element arranged to restrict the flow through the exhaust guide, an exhaust valve arranged to control a communication between the cylinder and the exhaust guide, and an exhaust valve actuation assembly for actuating the exhaust valve so as to perform in each of a plurality of cycles of the cylinder an exhaust valve actuation sequence, wherein the exhaust valve actuation assembly is adapted to control the commencement of the exhaust valve actuation sequence to occur selectively at any crankshaft angle within a non-zero crankshaft angle interval.

An engine system includes: a hydraulic valve stop mechanism configured to switch states of an intake valve and exhaust valve of a same stopped cylinder; a hydraulic pressure changing device configured to change hydraulic pressure supplied to the valve stop mechanism; and a valve control portion configured to control the hydraulic pressure changing device. When a return from a reduced-cylinder operation to an all-cylinder operation is requested, and an engine revolution is less than a reference revolution, the hydraulic pressure is changed such that opening of one of the valves of the stopped cylinder able to restart at an earlier stage is first restarted. When the return is requested, and the engine revolution is not less than the reference revolution, the hydraulic pressure is changed such that opening of the exhaust valve of the stopped cylinder is restarted before opening of the intake valve.

Systems and methods for operating an engine that includes a canister for storing fuel vapors are disclosed. In one example, one or more engine cylinders are deactivated in response to a level of fuel vapors stored in a fuel vapor storage canister when deceleration fuel shut off conditions are met. By deactivating one or more engine cylinders with closed intake and exhaust valves, it may be possible to reduce fuel vapors drawn into engine cylinders to reduce the possibility of cylinder misfire.

Systems and methods for operating an engine with deactivating valves are presented. In one example, deactivated valves may be reactivated to increase a rate of camshaft phase indexing relative to engine crankshaft position. However, if a desired rate of camshaft indexing is low, the engine cylinders may remain deactivated based on the low rate of desired camshaft indexing.

The present disclosure provides a system and a method for controlling valve timing of a continuous variable valve duration engine, including: classifying a plurality of control regions based on engine load and speed; applying a maximum duration to an intake valve and a long duration to an exhaust valve in a first control region; maintaining a maximum valve overlap in a second control region; advancing intake valve closing (IVC) timing and exhaust valve closing (EVC) timing in a third control region; applying a short duration to the exhaust valve and controlling the IVC timing to bottom dead center in a fourth control region; controlling a throttle valve to be fully opened, and controlling the IVC timing to an angle after BDC in a fifth control region; and applying the long duration to the exhaust valve, and controlling the IVC timing to prevent knocking in a sixth control region.

A controller of an internal combustion engine receives a request for engine braking and, in response thereto, activates an exhaust braking subsystem. Additionally, after passage of a period of time, the controller further activates a compression release braking subsystem. The period of time is preferably selected to permit development of increased back pressure in an exhaust system of the internal combustion engine prior to activation of the compression release braking subsystem. Additionally, following activation of the exhaust braking subsystem, the controller may whether the exhaust braking subsystem has failed and, if so, cause the compression release braking subsystem to operate in a reduced braking power mode, for example at less than full braking power potentially down to and including no braking power.

A method to ignite a gaseous fuel in an engine of an engine system is disclosed. The method includes introducing a compound having a peroxide group into a main combustion chamber of the engine for igniting the gaseous fuel. Further, the method includes controlling, by a controller, one or more parameters of the engine system to attain a temperature in the main combustion chamber within a temperature range. The compound decomposes into a radical, thus facilitating ignition of the gaseous fuel.

A control apparatus for an internal combustion engine, which, in the case of intake-side and exhaust-side cleaning controls being performed, is capable of ensuring stable combustion of a mixture when the engine is returned from a decelerating FC operation to a normal operation, thereby making it possible to enhance marketability. The control apparatus for the engine includes an ECU. The ECU performs intake-side cleaning control for controlling an intake cam phase CAIN to a predetermined most advanced value CAIN_ADV so as to increase a valve overlap period of an intake valve and an exhaust valve, and performs exhaust-side cleaning control for controlling an exhaust cam phase CAEX to a predetermined most retarded value CAEX_RET so as to increase the valve overlap period of the intake valve and the exhaust valve. Further, during execution of one of the intake-side and exhaust-side cleaning controls, the ECU inhibits execution of the other.

A switching roller finger follower for valve actuation comprises a pair of outer arms comprising an axle mounting. A bridge portion joins the pair of outer arms. A latch assembly comprises a ferrule. The ferrule is configured to reciprocate in a latch recess. An inner arm is pivotably mounted to a main axle and comprises a bearing rotatably mounted to a bearing axle. The bearing is configured to transfer forces from a cam lobe to the inner arm. A catch on the inner arm is configured to latch against the lip when the ferrule is in a first position. The catch can pivot past the ferrule when the ferrule is in a second position.

Intake holes at the opposite ends are opened and closed by first intake valves. The middle intake hole is opened and closed by a second intake valve. A control device includes an intake variable valve device. First branch channels are connected to the intake holes and produce a normal tumble flow. A second branch channel is configured such that the flow rate of intake air passing through the middle intake hole is relatively greater on the side closer to the outer periphery of the combustion chamber. Where increasing the flow coefficient is given a higher priority, a three-valve drive mode is selected. Where the strength of the normal tumble flow is enhanced, a two-valve drive mode is selected. Where production of the normal tumble flow is reduced, a one-valve drive mode is selected.