Changan 1.5 clean engine with high idle speed.

There are 1 reasons for the high idle speed of automobiles. When the engine water temperature is low, the air conditioner is turned on and the engine voltage is low, ECU programming should appropriately increase the idle speed. Under this normal condition, if the engine water temperature is normal, the air conditioner is turned off but the idle speed is high, it means that the system is faulty, which may be an electronic control system or a mechanical system. 2. If the idle speed is too high due to mechanical failure, it is necessary to check whether the air inlet pipe leaks and whether the vacuum tube falls off or is damaged. Because the air intake is small when the engine is idling, if there is air leakage, the idling speed will be high. 3. After cleaning the throttle body and idle speed control valve, the idle speed may be high after starting, which will give the computer a learning process, because the engine idle speed will drop after the throttle body and idle speed control valve are dirty. In order to stabilize the idle speed, ECU will control the idle speed control valve or throttle opening to increase the intake air, thus stabilizing the idle speed. After cleaning, the ECU also controls the air intake according to the original opening, and the engine idle speed will increase.