If an engine coolant temperature is equal to or lower than a first low-temperature determination value and a battery temperature is equal to or lower than a second low-temperature determination value when a request to start up an engine is made, the advancement driving of a variable valve operating mechanism is first started. Then, when an advancement amount of the variable valve operating mechanism later becomes equal to or larger than a prescribed startup start determination value, is started.

Methods and systems are provided for reducing torque pulsations during hybrid engine shutdown and restarts. A valve actuating mechanism may be actuated to operate an engine with a selected valve lift profile during engine restart and shutdown events that is distinct from the valve lift profile applied during cylinder combustion. The selected valve lift profile reduces cylinder pressure during engine shutdown and restarts.

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.

Methods and systems are provided for actuating an advanced cam profile switch (CPS) assembly. In one example, a system may include a first cylinder and a second cylinder of the CPS assembly that may be independently coupleable to a valve stem via two separate locking mechanisms. A first cam may be selectively engage with the first cylinder and the valve stem and a second cam may be selectively engaged with the second cylinder and the valve stem.

A method includes determining a value of an operational motor current limit and setting a value of a startup current limit equal to a predetermined value in excess of the value of the operational motor current limit if a set of predetermined conditions is satisfied. The method includes determining that operation of the engine has been interrupted, operating the electric motor of the variable valve timing mechanism with a current having a magnitude that is less than or equal to the startup current limit after determining that operation of the engine has been interrupted, determining that operation of the engine has resumed, and operating the electric motor of the variable valve timing mechanism with a current having a magnitude that is less than or equal to the operational motor current limit after determining that operation of the engine has resumed.

A valve opening and closing timing control device includes a driving-side rotating body, a driven-side rotating body, a stopper configured to determine a mechanical limit of a displacement region of a relative rotation phase, a phase control mechanism configured to change the relative rotation phase, and a control unit configured to control the electric motor so as to displace the actual phase detected by a phase sensor. A limit phase at which the stopper reaches an abutting state is set in advance when rotation of the electric motor is stopped while the internal combustion engine operates. Upon executing stop control of stopping the internal combustion engine, except when the actual phase is already the limit phase, the control unit executes braking control of limiting the rotation of the electric motor by controlling an electric current to be supplied to the electric motor.

A method for starting an internal combustion engine and a motor vehicle are provided. The internal combustion engine includes a plurality of cylinders. To start the internal combustion engine while deactivated, a predefined amount of working gas is introduced into the cylinder that fires first. A crankshaft of the internal combustion engine is driven by an electric motor and by the movement of a piston coupled to the crankshaft and associated with the cylinder that fires first to introduce the predefined amount of working gas. Subsequently, the internal combustion engine is started by the ignition of a mixture including the predefined amount of working gas and a predefined amount of fuel inside the cylinder that fires first.

A split cycle internal combustion engine includes a combustion cylinder accommodating a combustion piston and a compression cylinder accommodating a compression piston. The engine also includes a controller arranged to receive an indication of a parameter associated with the combustion cylinder and/or a fluid associated therewith and to control an exhaust valve of the combustion cylinder in dependence on the indicated parameter to cause the exhaust valve to close during the return stroke of the combustion piston, before the combustion piston has reached its top dead centre position (TDC), when the indicated parameter is less than a target value for the parameter; and close on completion of the return stroke of the combustion piston, as the combustion piston reaches its top dead centre position (TDC), when the indicated parameter is equal to or greater than the target value for the parameter.

If an engine coolant temperature is equal to or lower than a first low-temperature determination value and a battery temperature is equal to or lower than a second low-temperature determination value when a request to start up an engine is made, the advancement driving of a variable valve operating mechanism is first started. Then, when an advancement amount of the variable valve operating mechanism later becomes equal to or larger than a prescribed startup start determination value, is started.

A method of determining a condition of a component (e.g., valves) of an engine having a manifold air pressure sensor during a cold test includes providing pressurized air to an intake of the engine. The method includes rotating a crankshaft of the engine. The method includes measuring pressures with the manifold air pressure sensor as a function of crankshaft rotational position. The method includes comparing the pressures with a predetermined baseline. The method includes indicating a condition of the component based on the comparison of the pressures with the baseline.