A method for controlling an engine variable valve timing of a hybrid electric vehicle, may include providing a cam position setting table of a fuel efficiency prioritized intake/exhaust cam control mode, and a cam position setting table of a normal intake/exhaust cam control mode, the cam position setting table of the fuel efficiency prioritized intake/exhaust cam control mode being differentiated from the cam position setting table of the normal intake/exhaust cam control mode; selecting one of the fuel efficiency prioritized intake/exhaust cam control mode and the normal intake/exhaust cam control mode by a canister loading amount and whether or not diagnosis of an intake cam and diagnosis of an exhaust cam are completed; and determining position control values of the intake and exhaust cams by using the cam position setting table and then controlling positions of the intake cam and the exhaust cam by the determined position control values.

Methods and systems are provided for a pressure tapping device for a motor vehicle where a portion of the pressure energy generated at the fuel storage reservoir is transmitted to a working medium, physically separate from the fuel via the pressure tapping device. The pressure tapping device is fluidically coupled to a pressure actuator and enables the pressure operation via transmission of the pressure energy and adjustment of valves diverting flow from the fuel storage reservoir to the engine intake through the pressure tapping device.

A control device calculates an estimate of negative intake pressure based on the relationship between the rotation speed of a crankshaft and a throttle opening degree (Step S24). Then, the control device sets the estimate PE of the negative intake pressure, which is calculated in Step S24, to a greater value as combustion efficiency of CNG used in engine operation becomes higher (Step S25). When the corrected estimate PE of the negative intake pressure becomes smaller than or equal to a reference value PTh (Step S26: YES), the control device starts a negative pressure recovery procedure (Step S27).

Methods and systems are provided for improving the efficiency of canister purge completion. Based on engine operating conditions, a canister is purged to a compressor inlet or a throttle outlet. During purging conditions, as canister loads change, a purge flow through the canister is varied so that a fixed preselected portion of total engine fueling is delivered as fuel vapors.

Methods and systems are provided for vacuum generating devices. In one example, a system includes a vacuum generating device having an annular venturi passage located between two identical halves.

Various systems and methods are described for generating vacuum within an engine intake. A system may comprise an intake throttle including a slidable throttle valve, where the throttle valve may comprise a hollow interior passage, which in turn may be coupled to a vacuum consumption device. When vacuum is demanded by the vacuum consumption device, the throttle valve may be displaced downstream within the throttle to decrease airflow through the throttle and vacuum may be generated at tip of the throttle valve by flowing intake air between the throttle valve and a throttle fixture.

Systems and methods are described for controlling an aspirator control valve in an engine. An example method comprises closing the aspirator control valve responsive to diagnosing a first engine degradation condition and opening the aspirator control valve in response to diagnosing a second engine degradation condition.

A controller puts an internal combustion engine in a first induction control state in which a lift amount of an inlet valve is equal to or smaller than a predetermined amount and an opening of a throttle valve is larger than a predetermined opening with respect to a predetermined running state. The controller puts the internal combustion engine in a second induction control state in which the lift amount of the inlet valve is larger than the predetermined amount and the opening of the throttle valve is equal to or smaller than the predetermined opening with respect to the predetermined running state. An automatic stopper automatically stops the internal combustion engine in when the lift amount of the inlet valve is equal to or smaller than the predetermined amount, when a stopping condition of the internal combustion engine is met under which a predetermined vehicle state is produced.

A gas flow adjusting device is provided, which includes a tube body, a first horizontal shaft, a second horizontal shaft, two leaf structures, a torsional spring and two linkage assemblies. The first and second horizontal shafts are disposed in an accommodating space of the tube body and spaced apart from each other along an axial direction of the tube body. The leaf structures are pivoted on the first horizontal shaft and have a swinging direction identical to the axial direction. The torsional spring is sleeved around the second horizontal shaft and provides a resilient force along the axial direction. The linkage assemblies are connected to the leaf structures respectively, and each of the linkage assemblies is connected to the second horizontal shaft and the torsional spring. Therefore, when the leaf structures swing to different angles, the twisting amounts of the torsional spring are minimally varied.

Various systems and methods are described for generating vacuum within an engine intake. A system may comprise an intake throttle including a slidable throttle valve, where the throttle valve may comprise a hollow interior passage, which in turn may be coupled to a vacuum consumption device. When vacuum is demanded by the vacuum consumption device, the throttle valve may be displaced downstream within the throttle to decrease airflow through the throttle and vacuum may be generated at tip of the throttle valve by flowing intake air between the throttle valve and a throttle fixture.