How to solve the problem that China frv always has unstable idle speed repeatedly?

Usually, the main reasons for this idle speed fluctuation are:

1. The throttle valve is too dirty. Due to frequent starting of vehicles, short-distance driving, low temperature and poor fuel combustion quality, there will be too much carbon deposit and dirt on the throttle and the surrounding air intake, and the cross-sectional area of the air passage will change, which will make the control unit unable to accurately control the idle intake, resulting in the mixture being too rich or too thin, which will lead to idle fluctuation caused by abnormal combustion.

2. Leakage of intake manifold and valve. When air, gasoline vapor and combustion waste gas that should not enter enter the intake manifold, the mixture will be too rich or too thin, which will cause abnormal engine combustion and idle speed fluctuation.

3. Idle air actuator parts are faulty, which leads to inaccurate idle air control. Common causes are: the throttle motor is stuck or damaged.

4. The air quality is not allowed, the air flowmeter is too dirty or its line fault leads to the inaccurate control of engine idle intake, which makes the engine burn abnormally, which is the indirect cause of unstable idle speed.

5. Memory of idle speed value. When the ignition switch is turned on, the throttle control harness is in poor contact and the throttle is disassembled. If the battery is parked for too long or the battery pile head is disconnected for too long, the idle memory value stored in the engine control unit will be lost, resulting in the idle value rising and falling.