The invention relates to controlling engine braking of an internal combustion engine wherein the method includes setting the engine in an engine braking mode comprising i) interrupting fuel supply to a first cylinder, ii) restricting the flow of gas through an exhaust duct using an adjustable flow restricting member, and iii) controlling inlet and exhaust valves of the first cylinder in a compression-release mode comprising controlling the valves to compress gas in a combustion chamber when the piston moves towards the top dead center position (TDC) and release compressed gas into the exhaust duct when the piston is near the TDC. The method includes, prior to ii and iii: reducing a total gas mass flow rate through the engine by controlling, for at least one of valve, reducing a valve lift and/or adjusting a timing of a valve opening or closing so as to reduce the gas mass flow rate through the cylinder.

A lift regulator for a variable lift valve gear has a cam contour arranged around an axis of rotation of the lift regulator for deflecting a lift adjustment of the valve gear on rotation of the lift regulator about the axis of rotation. The cam contour has a region deflecting from a resting position, a changeover region, and a region deflecting back to the resting position. A variable lift valve gear and a method for operating the variable lift valve gear are disclosed.

A method and apparatus according to the invention is described, which in a first mode operates as an internal combustion engine delivering energy and in a second mode operates as a pulsed compression reactor converting electrical energy in the form of chemical compounds. In the second mode, at least one of the generated compounds is collected and temporarily stored.

A system and method of controlling a turbocharged engine system includes receiving a boost mode selection signal and controlling the turbocharged engine system in response to the boost mode selection signal.

Systems and methods for operating an engine that is started via expansion stroke combustion are described. In one example, the method increases air flow through the engine during an engine stopping process so that a larger amount of air may be trapped in a cylinder that is on its expansion stroke so that greater amounts of engine torque may be provided during engine starting.

A method of operation of exhaust valves of an adjustable exhaust port 2-stroke motorcycle engine with a two stage exhaust valve system includes: providing a control rod mechanically coupled to a governor, so that the governor causes a rotation of the control rod. A first stage exhaust valve, a second stage left exhaust valve, and a second stage right exhaust valve are also controllably linked to the control rod; and operating the second stage left exhaust valve and the second stage right exhaust valve by opening at least one of the second stage left exhaust valve and the second stage right exhaust valve before the first stage exhaust valve is completely open in an overlap operation. Related methods and structures for overlap, and/or stagger, and/or limiter operation of exhaust valves of an adjustable exhaust port 2-stroke motorcycle engine are also described.

An engine assembly and a method of control thereof is provided. The engine assembly comprises: an exhaust gas aftertreatment device having an inlet for receiving exhaust gases leaving an engine; a heater for selectively heating gases at or upstream of the exhaust gas aftertreatment device; an air moving device for driving a flow of gases into the inlet of the exhaust gas aftertreatment device when the engine is in a non-running condition; and a controller configured to, prior to the engine being started: operate the heater to heat gases at or upstream of the inlet; and operate the air moving device to drive a flow of gases into the inlet to thereby heat the exhaust gas treatment device.

A method for controlling a valve arrangement for an internal combustion engine, the valve arrangement including a piston arrangement comprising a piston having a piston end portion facing an inlet valve of the valve arrangement. The method includes receiving a signal indicative of a temperature level of an exhaust gas after treatment system and when the signal indicates a temperature level below a predetermined threshold level: advancing an exhaust event of the internal combustion engine; and controlling the piston arrangement for reducing the distance between the piston end portion and the inlet valve before the internal combustion engine assumes an air intake event.

Systems and methods for stopping an engine of a vehicle are described. In one example, the method anticipates when an engine is expected to stop and modifies engine operation so that less fuel is in the engine's intake ports when the engine is stopped so that the fuel may not escape the engine when the engine is restarted.

A stop/start system and method for an engine of a vehicle include a valve control system configured for full lift control of respective intake and exhaust valves of a plurality of cylinders of the engine and a controller of the engine configured to perform an engine stop event including initiating a fuel shutoff (FSO) event whereby fueling to the engine is disabled and the engine fully stops after a stop period and, in response to initiating the FSO event, commanding the valve control system to close each intake valve prior to closing its respective exhaust valve to (i) expel any residual gases from the cylinders during respective exhaust strokes prior to closing the respective exhaust valves, and (ii) prevent air-only intake and compression within the cylinders during the stop period to thereby mitigate or eliminate noise/vibration/harshness (NVH) caused by the air-only intake and compression.