A variable valve lift (VVL) system for an internal combustion engine is provided that utilizes hydraulic fluid supply pressure feedback to provide noise free operation. The VVL system includes a high pressure pump, a solenoid valve, a pressure translating device, a one-way valve, and a hydraulic fluid pressure sensor. The high pressure pump is fluidly connected to the solenoid valve and pressure translating device by at least one fluid gallery that forms a high pressure chamber. The solenoid valve selectively fluidly connects the high pressure chamber to a middle pressure chamber formed by at least one fluid gallery that fluidly connects the one-way valve to the solenoid valve. The hydraulic fluid pressure sensor is arranged to detect a hydraulic fluid supply pressure of the one-way valve and provides feedback to an electronic controller that determines a proper fluid intake opening timing of the solenoid valve.

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.

An apparatus for intake and exhaust of an engine includes: an outer tube including an outer-tube close end, an outer-tube open end, and a first outer-tube aperture set including a first aperture and a first outer-tube aperture group, an inner tube positioned in the outer tube about a concentric line, including an inner-tube close end, an inner-tube open end, and a first inner-tube aperture set including a second aperture and a first inner-tube aperture group, in which the inner-tube close end is proximate to the outer-tube close end, and a shaft connected to the inner-tube open end for rotating the inner tube in the outer tube about the concentric line, in which when the inner tube rotates, the second aperture sweeps across a portion of the first aperture and the first inner-tube aperture group sweeps across a portion of the first outer-tube aperture group.

Systems and methods for controlling operation of deactivated engine cylinders are presented. In one example, intake valve timing of deactivated engine cylinders is advanced to reduce amplitudes of intake pressure pulsations while exhaust valves of the deactivated engine cylinders are held closed. Further, intake valve timing of deactivated cylinders may be advanced responsive to output of an intake manifold pressure sensor.

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 for measuring at least one of temperature and pressure within a cylinder of an internal combustion engine can include an engine valve and a sensor. The internal combustion engine can include a valvetrain having rocker arm assembly, a camshaft, a valve, and a hydraulic lash adjuster. The engine valve can have a valve head and a valve stem extending from the valve head in an axial direction. The valve head can have a valve face configured to be in pressure communication with an engine cylinder. The valve stem can have an outer surface with a cylindrical portion and a variably-shaped portion. The variably-shaped portion can define a target detectable by the sensor and the sensor can be installed adjacent to the target. Alternatively, the sensor can be positioned to detect a level of force at some point along the valvetrain.

Systems and methods for controlling operation of deactivated engine cylinders are presented. In one example, intake valve timing of deactivated engine cylinders is advanced to reduce amplitudes of intake pressure pulsations while exhaust valves of the deactivated engine cylinders are held closed. Further, intake valve timing of deactivated cylinders may be advanced responsive to output of an intake manifold pressure sensor.

A method is disclosed for controlling an internal combustion engine having a first adjustable camshaft for the actuating of first valve elements of the internal combustion engine. An effect of an actuation at least of a first valve element by the first camshaft on this valve element is detected. An actual position of the first camshaft and/or of a crankshaft driving the latter is detected on the basis of this detecting of the effect. An adjustment of the first camshaft is calibrated on the basis of a first deviation between this detected actual position and a predetermined required position.

A system and method for diagnosing malfunctions in a variable valve actuation device. The method uses a rocker arm assembly with a hydraulically operated latch for latching together first and second arms of the rocker arm assembly when latched. The rocker arm assembly includes a source of pressurized fluid connected to a hydraulic valve that provides fluid high or low pressure fluid to the hydraulically-operated latch. A control gallery connects the hydraulic valve to the latch. A pressure transducer is positioned within the gallery and is adapted to create a signal indicating the pressure in the gallery. A control unit is coupled to the hydraulic valve and the pressure transducer. The control unit is adapted to sense engine operation parameters, actuate the hydraulic valve, read the signal from the pressure transducer; and identify malfunctions of the rocker arm assembly based upon the signal from the transducer.

A novel latch seat for a switching rocker arm assembly used in variable valve actuation (VVA) systems for internal combustion engines. The seat is formed interactively in the assembled switching rocker arm using a novel fixture and press. The press interactively creates a curved dimple of the correct curvature, position and depth while measuring several lash dimensions. Since the latch seat is formed on the assembled rocker arm assembly, the latch seat depth is designed to account for the inaccuracies in the rocker arm assembly parts which create lash. Therefore all of the parts may be made with less precision since the latch seat is sized to compensate for the inaccuracies of all of the parts. The rocker arm assembly parts now may be manufactured to less stringent standards, but result in a rocker arm assembly with same accuracy of rocker arm assemblies manufactured to previous standards.