Methods and systems are provided for removing entrapped air from oil flowing within a valve deactivation hydraulic circuit of an engine. In one example, the system may include a cylinder head cap, a variable displacement engine oil control valve (VDE OCV), a variable control timing oil control valve (VCT OCV), a rocker arm, a switch of the rocker arm, a pressure relief valve and a switch of the pressure relief valve, the cylinder head cap having an inbound interior surface of the cylinder head cap, the valve deactivation hydraulic circuit having a switching gallery and a hydraulic lash adjuster oil gallery. The hydraulic lash adjuster oil gallery may provide oil pressure communication to the switching gallery, the hydraulic lash adjuster oil gallery, the switch of the rocker arm, the switch of the pressure relief valve, the VDE OCV, and the VCT OCV.

An internal combustion engine includes a cylinder and a valve assembly configured to activate and deactivate the at least one cylinder. The valve assembly includes an intake valve configured to control air flow into the at least one cylinder. A controller outputs a first control signal to the valve assembly to deactivate the at least one cylinder in response to detecting a deceleration event. The controller also outputs a second control signal to command the valve assembly to delay opening the intake valve from a closed position after re-activating the cylinder so that the torque output produced in response to re-activating the cylinder is reduced.

A control method of valve opening and closing for an engine of which an intake continuous variable valve duration (CVVD) apparatus and an intake continuous variable valve timing (CVVT) apparatus are provided on the intake side, and an exhaust continuous variable valve duration (CVVD) apparatus and an exhaust continuous variable valve timing (CVVT) apparatus are provided on the exhaust side. The control method includes: determining, by a controller, a driving region among a predetermined plurality of driving regions according to a speed and a torque of the engine; and controlling, by the controller, opening timing, closing timing, and opening duration of each of an intake valve and an exhaust valve according to the driving region of the engine. The intake valve closing (IVC) timing is before a bottom dead center (BDC) in all driving regions.

Systems and methods to extend a life of a component of a cylinder deactivation system are provided. A method includes generating, by a controller, an initial life factor for the component; initiating, by the controller, a CDA mode for an engine; determining, by the controller, an actual life factor for the component, the actual life factor determined by comparing a number of switching events of a cylinder in the CDA mode to a number of cycles of the cylinder in the CDA mode; comparing, by the controller, the actual life factor to the initial life factor; and modifying, by the controller based on the comparison, operation of the engine in the CDA mode to adjust the actual life factor.

In a control device and a control method for a variable valve timing mechanism according to the present invention, the rotational phase of a camshaft is measured based on the cam angle signal and crank angle signal upon receiving each pulse of the cam angle signal, and the rotational phase change over time within a period of the cam angle signal is measured based on the motor angle signal. It is decided whether the cam angle signal and/or crank angle signal has a prescribed pulse pattern at a diagnostic timing that comes after the last pulse of the cam angle signal. When this decision result is positive, it is then decided whether the motor angle sensor operates normally or abnormally based on the rotational phase and the amount of rotational phase change that are measured when the last pulse of the cam angle signal is received before the diagnostic timing.

Described herein is a system for variable actuation of an engine valve of an internal-combustion engine, where the system is able to actuate the engine valves, selectively, in a four-stroke operating mode and in a two-stroke operating mode, on the basis of the operating conditions of the engine.

A variable valve timing control device includes a phase detecting portion; a phase control portion driving an electromagnetic solenoid while obtaining a detection signal detected by the phase detecting portion to set a spool to one of a phase control region and a lock region; and a boundary memory portion memorizing a boundary electric current value for referring a boundary between the phase control region and the lock region when the phase control portion operates a phase control; and a characteristic calculation portion obtaining the boundary electric current value by calculation, the boundary electric current value supporting the boundary between the phase control region and the lock region based on solenoid characteristic information of the electromagnetic solenoid and valve characteristic information of an electromagnetic control valve, the characteristic calculation portion memorizing the boundary electric current value to the boundary memory portion.

A cam-switching device switches between first and second cams provided so as to correspond to intake exhaust valves of an engine. In a case of switching from the first cam to the second cam, a cylinder resting unit stops the opening and closing operations of the intake and exhaust valves in the same combustion cycle, and a cam shaft moving unit starts sliding the cam shaft in a first cam angle range. In a case of switching from the second cam to the first cam, the cylinder resting unit stops the opening and closing operations of the intake and exhaust valves in the same combustion cycle, and the cam shaft moving unit starts sliding the cam shaft in a second cam angle 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.

Methods and systems are described for an engine with a cam torque actuated variable cam timing phaser. Phaser positioning control is improved by reducing inaccuracies resulting from inadvertent spool valve and/or phaser movement when the spool valve is commanded between regions. In addition, improved spool valve mapping is used to render phaser commands more consistent and robust.