Vehicle idle speed control is mainly divided into several forms.

Idle speed control is to change the air intake of the engine at idle speed. There are generally two ways to change the intake: the way to change the intake bypass is bypass, most of the early EFI gasoline engines are bypass, and the way to directly control the throttle is direct-acting throttle, which is now electronic throttle. Due to the advantages of compact structure and accurate control, electronic throttle has been fully assembled on the gasoline engine of advanced cars, and it is only a matter of time before it replaces the bypass throttle. Bypass type According to the different driving modes of actuators, idle actuators with bypass air intake adjustment mode can be divided into stepper motor type, rotary solenoid valve type, duty ratio control type vacuum on-off valve and switch control type vacuum on-off valve.