Engine idle control system

摘要

An engine idle control system includes an improved construction for changing an aimed idle engine speed, which is preset by the manufacturer therein, in response to various needs of a user. The engine has a main passage having a throttle valve therein and a bypass passage arranged to bypass the throttle valve. The bypass passage supplies an idle air charge to a combustion chamber of the engine when the throttle valve is generally closed and has an adjusting valve therein for adjusting the idle air charge. A control device controls the adjusting valve to reduce a difference between an actual idle speed sensed by an engine speed sensor and an aimed idle speed preset in the control device. The control device includes means for changing the aimed idle speed.