Schematic diagram of automobile idle valve in this position

The idle speed control valve is installed on the vent hole beside the throttle. According to the ignition signal, when the engine speed is lower than 750 rpm, the idle control valve will be activated in time to increase the engine speed, and when the engine speed exceeds 1050 rpm, the idle control valve will stop working.

In vehicles equipped with air conditioning system, this control valve is also called idle acceleration valve. After the air-conditioning compressor operates, the engine load is generated, which reduces the engine idle speed, and the idle speed control valve acts accordingly to maintain the idle speed stability. When the idle speed control valve fails, it may cause various problems of the vehicle, and even make it unable to work in some cases.

Extended data

Idle speed control valve function

When the idle load of the engine increases, ECU controls the idle control valve to increase the air intake, thus improving the idle speed and preventing the engine from being unstable or flameout; When the idle load of the engine is reduced, ECU controls the idle control valve to eliminate the empty space, thus reducing the idle speed and avoiding excessive idle speed.

The idle speed control valve is installed on the bypass air hole of the bone air valve. According to the ignition signal, the idle controller makes the idle control valve act in real time when the engine speed is lower than 750 rpm, so as to increase the engine speed, and stops acting when the engine speed exceeds 1050 rpm. This control valve is also called idle acceleration valve in vehicles with refrigeration system. After the refrigeration compressor operates, the engine load breeds, which makes the engine idle at a low level, and the idle speed control valve acts accordingly to maintain the idle speed stability.

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