17 what does Qi Jun fault code ISC idle mean?

LSC is idle speed control valve fault. Clean or replace the idle speed control valve, and basically set the idle speed with a special MA resolver. If you hear the sniffing sound of the intake pipe, it proves that there is a leak in the intake system. Find the leakage point and reseal or replace the phase parts.

LSC is an idle speed control valve.

Working principle of idle speed control valve: the 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 will be energized and the circuit of the engine computer controller will be grounded. When the operating parameters of the engine deviate from the normal value, the valve is used to adjust the idle speed, and the idle speed is adjusted by controlling the amount of air bypassing the throttle body. After the engine is started,

When the idle control valve is opened for a period of time, the air intake increases, which increases the idle speed of the engine by about 150 rpm and reaches 300 rpm. When the engine coolant temperature is low, the idle speed control valve is opened to obtain a suitable fast idle speed. According to different coolant temperatures, the computer controls the position of the plunger of the idle speed control valve by changing the signal intensity transmitted to the idle speed and control valve.

The idle speed control valve of stepping motor is the most widely used idle speed control device in the world at present, which is used to open the bypass air passage of the automobile EFI system and adjust the bypass air volume to make the engine speed reach the required target value. In principle, it consists of a rotor composed of permanent magnets, a stator composed of excitation coils, a feed screw and a valve that can convert rotary motion into linear motion.