A variable valve timing control device has, as control modes for adjusting inflow and outflow of oil with an OCV, a lock mode for moving a lock pin in a locking direction, a phase control mode for controlling a camshaft phase by a target phase in accordance with an operation state of an engine, and an oil filling mode for filling an advancement chamber and a retardation chamber with the oil in a state that the lock pin moves in the locking direction, before shifting from the lock mode to the phase control mode. When the oil filling mode has been selected, a target position of a spool is set based on viscosity of the oil, and the position of the spool is controlled so as to be the set target position.

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.

To provide a controller and a control method, for an internal combustion engine, that can detect occurrence of knocking appropriately, even though the frequency distribution of the knock signal is distorted according to the occurrence state of knocking. The controller for the internal combustion engine calculates the background level by processing a low pass filter to the knock signal; and performs a low side frequency increase which makes a low side frequency, which is a cutoff frequency of the low pass filter in the case where the knock signal is smaller than an output value of the low pass filter, higher than a high side frequency, which is a cutoff frequency of the low pass filter in the case where the knock signal is larger than the output value of the low pass filter.

The present disclosure provides a CVVT system including: an OCV supplying oil received from a cylinder block into a CVVT; an oil supply unit supplying oil from the OCV to a lock pin; and an actuator selectively opening or closing the oil supply unit such that oil is supplied to the lock pin and the lock pin is separated from a lock pin hole when the oil supply unit is opened.

An internal combustion engine includes an exhaust valve, a plurality of cams Ca, Cb, and Cc used to drive the exhaust valve, a cam-switching variable valve mechanism that selects a use cam used to drive the exhaust valve out of the plurality of cams Ca, Cb, and Cc, and an electronic control unit that determines whether switching abnormality of the use cam in the variable valve mechanism is present on the basis of a locus M in a predetermined period K which is a period in which the exhaust valve is opened. The locus M is a locus of an in-cylinder pressure changing rate dPc/dθ and is specifically a locus indicating a variation of the in-cylinder pressure changing rate dPc/dθ depending on a crank angle θ.

A rocker arm assembly constructed in accordance to one example of the present disclosure includes an outer rocker arm and an inner rocker arm. The outer rocker arm has a first roller configuration that rotates around a first axis. The inner rocker arm has a second roller configuration that rotates around a second axis. The inner rocker arm is configured to move between a latched and unlatched position relative to the outer rocker arm. One of the first and second axes is positioned for alignment over an engine valve. The other of the first and second axes is offset from the engine valve.

Methods and systems are provided for a valve lift control device. In one example, a method may include rotating an adjusting camshaft of the valve lift control device in order to adjust a valve lift of one or more cylinders.

An engine control system for a vehicle includes a target torque module that determines a target torque output of an engine based on at least one driver input. A target air per cylinder (APC) module determines a target APC for the engine based on the target torque. A target mass airflow (MAF) module determines a target MAF through a throttle valve of the engine based on the target APC, a number of activated cylinders of the engine, and a total number of cylinders of the engine. A throttle control module determines a target throttle opening based on the target MAF and controls opening of the throttle valve based on the target throttle opening.

A control method using a continuous variable duration apparatus provided to adjust opening duration of an intake valve of an engine includes: determining a reduction amount of a compression ratio to prevent knocking, when knocking of an engine is expected, setting a desired effective compression ratio required for the reduction amount of the effective compression ratio, setting desired duration for the set desired effective compression ratio, and controlling duration of the intake valve on the basis of the set desired duration.

A control method using a continuous variable duration apparatus provided to adjust opening duration of an intake valve of an engine includes: determining a reduction amount of a compression ratio to prevent knocking, when knocking of an engine is expected, setting a desired effective compression ratio required for the reduction amount of the effective compression ratio, setting desired duration for the set desired effective compression ratio, and controlling duration of the intake valve on the basis of the set desired duration.