Abstract: A system and method for controlling an internal combustion engine control an actuator in response to variations of intake airflow relative to an average intake airflow to manage induction acoustics. The system and method may include controlling an actuator, such as a throttle valve, to increase intake manifold vacuum in response to intake airflow. In an engine having electronically actuated intake and/or exhaust valves, intake airflow is estimated based on at least engine speed and valve timing and compared to a measured intake airflow to determine a first difference. The measured airflow is divided into a steady-state and transient term or component with a second difference determined based on the transient component and a target value. Throttle valve position is selectively controlled to increase vacuum in response to a combination of the first and second difference to manage induction acoustics.

Abstract: An idle air control valve for a vehicle includes a housing (21), a motor (32) disposed in the housing, a shaft (29) associated with the motor, and a bellows assembly (30) including a bellows structure (10) having a first end defining a base (14), a second, opened end (16), and a bellows (18) between the first and second ends. An annular rim member (28) is associated with the second opened end. A pintle (24) has surfaces defining an annular groove (26) therein. The annular rim member (28) is received, in press-fit engagement, in the annular groove (26). The base (14) is in press-fit engagement with a recess (22) in the housing and the pintle (24) is coupled with an end of the shaft, such that the bellows structure together with the pintle surround the shaft and provide a barrier substantially preventing contaminants from entering the motor.

Abstract: A system for controlling idle air flow for an engine. The system includes an idle air control valve, a stepper motor, and a controller. The idle air control valve has a first hard stop and a second hard stop. The stepper motor is coupled to the idle air control valve and configured to manipulate the position of the idle air control valve. The controller is in communication with the stepper motor to provide a driving signal. Further, the controller is configured to drive the idle air control valve to the first hard stop and then drive the idle air control valve to the second hard stop after receiving an engine shutdown command.

Abstract: To make a motor to control throttle valve opening degree compact and reduce electricity consumption, a throttle valve lever (4) attached to a throttle valve shaft (3) has a roller (4b) and an operating arm portion (4a), a loosely fitted lever (8) is arranged to the throttle valve shaft (3), the operating arm portion (4a) is arranged in a gap (S) between first and second locking portions (8a1, 8a2) of the loosely fitted lever (8), a cam surface (7a) of a cam lever (7) connected to an output shaft (Ma) of a lead screw type step motor (M) faces to the roller (4b), a throttle valve operating drum (11) is coupled to the loosely fitted lever (8) via a link cover (13) and, when the motor (M) is driven, the cam lever (7) rotates the throttle valve lever (4) and the arm portion (4a) rotates within the gap (S) to hold an idling opening degree.

Abstract: An idle speed control apparatus which improves freedom of selection in an opening degree characteristic of a throttle valve is structured such that an intake passage of a throttle body is opened and closed by a throttle valve, a cam lever is attached to one end of a rotatably supported link shaft, a link lever is attached to another end of the link shaft, a slider of a stepping motor is connected to the link lever, a cam portion of the cam lever is connected to a roller of the throttle valve lever, linear motion of the slider is transmitted to the link shaft via the link lever to rotationally displace the link shaft, rotation of the cam lever is transmitted to the throttle valve lever, and the throttle valve opens an idling opening degree corresponding to the rotation of the stepping motor.

Abstract: An idle speed control apparatus which improves freedom of selection in an opening degree characteristic of a throttle valve and is excellent in a resolving power with respect to an opening degree change of the throttle valve, is structured such that an intake passage (2) of a throttle body (1) is opened and closed by a throttle valve (4) attached to a throttle valve shaft (3) and is provided with a throttle valve lever (5) in an end portion of the throttle valve shaft (3), a cam lever (10) is attached to one end of a rotatably supported link shaft (9), a link lever (11) is attached to another end of the link shaft, a slider (12) of a stepping motor (M) is connected to the link lever (11), a cam portion (10A) of the cam lever (10) is connected to a roller (8) of the throttle valve lever (5), a linear motion of the slider (12) is transmitted to the link shaft (9) via the link lever (11) to rotationally displace the link shaft (9), a rotation of the cam lever (10) generated by the rotation of the link shaft (9)

Abstract: A sound attenuator is provided for an idle air control valve system in order to reduce noise emanating from the idle air control valve. The sound attenuator comprises a fibrous pad that is inserted into an air conduit of the idle air control system. In a preferred embodiment, the fibrous pad is inserted into the air conduit near the air inlet where the conduit receives air from a region upstream, or above the throttle plate. A small hole can be provided through the air inlet. In certain embodiments, the air inlet of the air conduit is an opening formed in an inner cylindrical surface of the throttle body. In alternative embodiments, the air inlet can be remote from the internal surface of the throttle body.

Abstract: An outboard motor powers a watercraft and comprises an engine mounted within an engine compartment. The engine comprises an induction system having an induction passage extending between an air intake box to a combustion chamber. A throttle valve is positioned along the passage. A bypass passage communicates with the passage at a location between the throttle valve and the combustion chamber. An adjustable valve controls flow through the bypass passage. The adjustable valve can be closed at a first rate if a the watercraft is traveling at a speed greater than a preset value and at a second rate if the watercraft is traveling at a speed below the preset value.