A method for controlling intake and exhaust valves of an engine may include: determining, by a controller, a target opening duration of the intake and exhaust valves based on an engine load and an engine speed; modifying, by an intake continuous variable valve duration (CVVD) device and by an exhaust CVVD device, current opening and closing timings of the intake valve and/or exhaust valve based on the target opening duration of the valves; and advancing or retarding, by the intake and/or exhaust CVVD devices, the current opening timing of the intake and exhaust valves while simultaneously retarding or advancing the current closing timing of the intake and exhaust valve by a predetermined value based on the target opening duration.

A method for diagnosing a variable valve timing system configured for enhancing precision of diagnosis regarding a variable valve timing system by precisely diagnosing whether an oil pressure detecting device of the variable valve timing system normally operates, may include a normal operation time determining operation of determining a normal operation time of an oil pressure detecting device to determine whether the oil pressure detecting device is normal after an engine starts, and a diagnosing operation of diagnosing whether the oil pressure detecting device is normal according to whether the oil pressure detecting device of the VVT system is turned off within the normal operation time or whether oil pressure reaches reference pressure.

A control device is configured, if, although the control device has caused a cam switching device to perform a first cam switching operation for switching the profiles of all the valve-driving cams of a plurality of cylinders from a first profile to a second profile, the profiles of all the valve-driving cams of the plurality of cylinders do not coincide with the second profile, to cause the cam switching device to perform a second cam switching operation for switching the profile of the valve-driving cam for at least one or more normal cylinders that are one or more cylinders at which the switching of profiles to the second profile has succeeded.

An oil supply control device for an engine includes: a hydraulic controller which outputs a control value to an adjusting device to cause a detected hydraulic pressure detected by a hydraulic pressure sensor to coincide with a predetermined hydraulic pressure value; a determination portion which compares an output control value output from the hydraulic controller to the adjusting device when the detected hydraulic pressure coincides with the predetermined hydraulic pressure value and a control value stored in a memory, to determine whether or not a difference between the output control value and the stored control value lies within a predetermined allowable range; and a device controller which allows activation of a hydraulic actuating device when an oil temperature is not lower than a first temperature in a case where the difference lies within the allowable range, inhibits activation of the hydraulic actuating device when the oil temperature is lower than a second temperature higher than the first temperature in a case where the difference does not lie within the allowable range, and allows activation of the hydraulic actuating device when the oil temperature is not lower than the second temperature in a case where the difference does not lie within the allowable range.

An oil supply control device includes: a memory which stores first master data constituted by predetermined control value; a hydraulic controller which outputs the control value to an adjusting device to cause a hydraulic pressure to coincide with a target hydraulic pressure; and a determination portion which determines whether or not a first difference between an output control value and the control value of the first master data lies within a predetermined allowable range, wherein the hydraulic controller starts to control the adjusting device with use of the control value of the first master data, when the first difference lies within the allowable range, and starts to control the adjusting device with use of the control value of second master data, when the first difference does not lie within the allowable range, the control value of the second master data causing the first difference to lie within the allowable range.

An apparatus includes a valve and an actuator. The valve has a portion movably disposed within a valve pocket defined by a cylinder head of an engine. The valve is configured to move relative to the cylinder head a distance between a closed position and an opened position. The portion of the valve defines a flow opening that is in fluid communication with a cylinder of an engine when the valve is in the opened position. The actuator is configured to selectively vary the distance between the closed position and the opened position.

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.

In a control device for an engine, the engine includes combustion chambers, ports connected to the combustion chambers, and valves that open and close areas between the combustion chambers and the ports. The control device includes an electronic control unit that is configured to execute an anti-freezing operation of performing control to fully close the valves or make the valves be in a state of being opened with a lift amount of 1 mm or more, in a case where temperatures around the valves are lowered to a predetermined temperature range after the engine is stopped, or in a case where an outside air temperature when the engine is stopped is equal to or lower than a predetermined temperature. The predetermined temperature range is a temperature range in which an upper limit value is lower than 10 C., and the predetermined temperature is lower than 5 C.

Systems, apparatuses and methods are disclosed that include an internal combustion engine including a plurality of cylinders operable by a valve actuation mechanism including a lifting mechanism having a compression brake valve profile configured to selectively lift the exhaust valves on a downstroke of the cylinders in response to a cranking condition of the internal combustion engine, wherein the compression braking valve profile is phased to the upstroke of the pistons.

A method for heating a sliding camshaft actuator at cold engine start wherein the sliding camshaft actuator includes at least one magnetic field generating coil having a core, a piston armature disposed in the core of the at least one magnetic field generating coil, a magnet in mechanical communication with the piston armature, and an actuator pin in mechanical communication with the magnet. The method includes detecting a cold engine start condition and reversing an energizing voltage on the at least one magnetic field generating coil when the outside temperature is below a predetermined temperature threshold. The reverse energizing voltage on the at least one magnetic field generating coil is maintained for a predetermined period of time to heat the piston armature, the magnet, and the actuator pin.