What is the main function of idle speed control valve and how does it work?

Idle speed control valve is powered by ignition switch. As long as the ignition switch is turned to the on position, the idle speed control valve is energized, and the engine computer controls its circuit to be grounded. This valve is used to adjust the idle speed when the working parameters of the engine deviate from the normal value. Idle speed is regulated by controlling the amount of air bypassing the throttle body. After the engine is started, the idle speed control valve is opened for a period of time, and the intake air is increased, so that the engine idle speed is increased by about 150r/min-300r/min. When the engine coolant temperature is low, the idle speed control valve is opened to obtain a suitable fast idle speed. The engine computer controls the position of the plunger of the idle control valve by changing the signal intensity sent to the idle control valve according to different coolant temperatures.

The idle speed control valve of stepping motor is one of the most widely used idle speed control devices in the world. It is used to open the bypass airway of automobile EFI system to adjust the bypass ventilation and make the engine speed reach the required target value. Structure principle: It consists of a rotor composed of permanent magnets, a stator composed of excitation coils, a lead screw and a valve that converts rotary motion into linear motion. It uses the stepping signal provided by the system to carry out conversion control, so that the rotor rotates forward or backward, and the valve core (screw) expands and contracts to achieve the purpose of adjusting the cross section of the bypass passage, thus stabilizing the idle speed and achieving the ideal idle speed.