Abstract: A system for controlling a variable valve lift system of an engine comprises a delay module that estimates a total delay based on at least one of a measured and an estimated delay of the variable valve lift system. A variable valve control module commands one of a first transition from a variable valve low-lift profile to a variable valve high-lift profile and a second transition from a variable valve high-lift profile to a variable valve low-lift profile based on the total delay.

Abstract: The apparatus of the present invention provides a lash adjuster feed channel for an engine assembly. The engine assembly includes first and second sets of hydraulic lash adjusters responsive to a variation in hydraulic fluid pressure to cause a variation in lift of first and second sets of engine valves respectively operatively connected thereto. The cylinder head defines a first feed passage in fluid communication with the first set of hydraulic lash adjusters, and a second feed passage in fluid communication with the second set of hydraulic lash adjusters. The valve lift of the first set of engine valves is independently variable by controlling the transfer of hydraulic pressure in the first feed passage, and the valve lift of the second set of engine valves is independently variable by controlling the transfer of hydraulic pressure in the second feed passage. A corresponding method is also provided.

Abstract: A diagnostic system for an engine includes a pressure monitoring module that determines a plurality of first average pressure values and a plurality of second average pressure values of a fluid supply provided to a camshaft phaser. A diagnostic module identifies one of a plurality of cylinders associated with a failed variable valve lift mechanism based on the first and the second average pressure values. Each of the first and the second average pressure values respectively correspond to each of the plurality of cylinders.

Abstract: A single hydraulic circuit module is provided for controlling valve lift at multiple cylinders in an engine. The single module includes a housing that at least partially forms a supply passage and a control passage. The supply passage is in fluid communication with the fluid supply and the control passage is in fluid communication with the feed passage. At least one solenoid valve is provided and supported by the housing positioned between the supply passage and the control passage. The solenoid valve is controllable to vary fluid flow from the supply passage to the control passage to permit adjustment of hydraulic lift assemblies to vary lift of engine valves in response to control of the solenoid valve.

Abstract: A diagnostic system for an engine includes a pressure monitoring module that determines a plurality of first average pressure values and a plurality of second average pressure values of a fluid supply provided to a camshaft phaser. A diagnostic module identifies one of a plurality of cylinders associated with a failed variable valve lift mechanism based on the first and said second average pressure values. Each of the first and the second average pressure values respectively correspond to each of the plurality of cylinders.

Abstract: A system for controlling a variable valve lift system of an engine comprises a delay module that estimates a total delay based on at least one of a measured and an estimated delay of the variable valve lift system. A variable valve control module commands one of a first transition from a variable valve low-lift profile to a variable valve high-lift profile and a second transition from a variable valve high-lift profile to a variable valve low-lift profile based on the total delay.

Abstract: The apparatus of the present invention provides a lash adjuster feed channel for an engine assembly. The engine assembly includes first and second sets of hydraulic lash adjusters responsive to a variation in hydraulic fluid pressure to cause a variation in lift of first and second sets of engine valves respectively operatively connected thereto. The cylinder head defines a first feed passage in fluid communication with the first set of hydraulic lash adjusters, and a second feed passage in fluid communication with the second set of hydraulic lash adjusters. The valve lift of the first set of engine valves is independently variable by controlling the transfer of hydraulic pressure in the first feed passage, and the valve lift of the second set of engine valves is independently variable by controlling the transfer of hydraulic pressure in the second feed passage. A corresponding method is also provided.

Abstract: The apparatus of the present invention provides a lash adjuster feed channel for an engine assembly. The engine assembly includes first and second sets of hydraulic lash adjusters responsive to a variation in hydraulic fluid pressure to cause a variation in lift of first and second sets of engine valves respectively operatively connected thereto. The cylinder head defines a first feed passage in fluid communication with the first set of hydraulic lash adjusters, and a second feed passage in fluid communication with the second set of hydraulic lash adjusters. The valve lift of the first set of engine valves is independently variable by controlling the transfer of hydraulic pressure in the first feed passage, and the valve lift of the second set of engine valves is independently variable by controlling the transfer of hydraulic pressure in the second feed passage. A corresponding method is also provided.

Abstract: A single hydraulic circuit module is provided for controlling valve lift at multiple cylinders in an engine. The single module includes a housing that at least partially forms a supply passage and a control passage. The supply passage is in fluid communication with the fluid supply and the control passage is in fluid communication with the feed passage. At least one solenoid valve is provided and supported by the housing positioned between the supply passage and the control passage. The solenoid valve is controllable to vary fluid flow from the supply passage to the control passage to permit adjustment of hydraulic lift assemblies to vary lift of engine valves in response to control of the solenoid valve.

Abstract: A method for diagnosing malfunctions of switching valve lifters includes sensing variations in pressure of trapped oil in a drive chamber of a hydraulic camshaft drive, such as a cam phaser, comparing peak oil pressure readings in the drive chamber resulting from the increased torque of opening the valves of various cylinders of an engine and identifying cylinders having lower than normal valve opening pressure readings, indicating failure of an associated valve lifter to properly actuate a valve of the cylinder. Apparatus for indicating such malfunctions could include a cam phaser with pressure chamber, a pressure sensor connected to indicate pressure variations in the chamber; and a pressure indicator connected to the sensor and adapted to indicate actual pressure variations for comparison with normal variations to identify low pressure peaks indicating malfunction of a switching lifter. A computer could be used to receive and act upon the malfunction indications.

Abstract: The invention provides a valvetrain configuration in an internal combustion engine in which a plurality of two-step rockers enable the engine poppet valves to switch between two lift profiles. In addition, a lost-motion stationary lash adjuster enables the deactivation of the engine poppet valve. The integration of a two-step rocker with a deactivating stationary lash adjuster yields a better control of the combustion process, under different engine operating conditions than what is achievable with either one of these actuators acting alone. Preferably, the locking and unlocking of the two-step rocker arm and deactivating stationary lash adjuster is controlled by two on/off hydraulic valves in a hydraulic circuit, and a piloted check valve prevents hard landings between stationary and moving components within the stationary hydraulic lash adjuster.

Abstract: Deactivation apparatus for selected cylinders of an engine include switching hydraulic lash adjusters or valve lifters forming part of a valve train for actuating engine valves of the selected cylinders and operable to actuate or release their respective valves in response to an oil pressure signal. A gallery carrying the lash adjusters includes oil passages fed by an engine pressure oil supply through a control valve to supply oil to switching portions of the lash adjusters. The control valve is operative to close or open communication of the oil supply with the lash adjusters and to relieve oil pressure in the passages when communication with the pressure oil supply is closed. Various bypass alternatives between the pressure oil supply and the oil passages carry oil to portions of the oil passages to purge air from the passages when the three-way valve exhaust port is open.

Abstract: An internal combustion engine includes hydraulically-controlled cylinder deactivation and has an engine block with a plurality of cylinders formed therein. At least one-half of the cylinders are deactivatable by collapsible lifters. An individual hydraulic circuit module is positioned adjacent each deactivatable cylinder. Each hydraulic circuit module includes a valve and is configured to receive a supply of oil from the engine block and to selectively provide pressurized oil to the respective collapsible lifters for cylinder deactivation. A solid cover plate is positioned adjacent each cylinder which is not deactivatable.

Abstract: An internal combustion engine includes hydraulically-controlled cylinder deactivation and has an engine block with a plurality of cylinders formed therein. At least one-half of the cylinders are deactivatable by collapsible lifters. An individual hydraulic circuit module is positioned adjacent each deactivatable cylinder. Each hydraulic circuit module includes a valve and is configured to receive a supply of oil from the engine block and to selectively provide pressurized oil to the respective collapsible lifters for cylinder deactivation. A solid cover plate is positioned adjacent each cylinder which is not deactivatable.