Why doesn't the car idle?

1, automobile battery voltage is low; Specific detection method: test the battery voltage with a voltage range of three meters. If it is lower than 10V, it is recommended to replace it. If it is around 1 1V, it is barely used; Be prepared to be replaced. 12V or more is ok.

2. Check whether it is caused by carbon deposition; If driving around 20000KM, check and clean the throttle.

3. Check, test and replace the spark plug.

4. The control unit receives an error signal and sends an error command, which leads to inaccurate idle intake control of the engine and abnormal engine combustion.

5. Failure of idle air actuator leads to inaccurate idle air control.

Extended data:

Treatment method of continuous high idle speed of automobile

1. 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 not turned on, and 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, be sure to check whether the intake pipe leaks, whether the vacuum pipe falls off and whether the intake pipe is damaged (the intake manifold of Volkswagen engine is mostly rubber pipe). Because the air intake of the engine is very small at idle speed, if there is air leakage, it will cause high idle speed.

3. After cleaning the throttle body and idle speed control valve, the engine may have a high idle speed after starting, which requires a learning process for the computer. Because the engine idle speed will decrease after the throttle body and idle speed control valve are dirty, in order to stabilize idle speed, ECU will control the opening of idle speed control valve or throttle valve to increase the intake air, thus stabilizing idle speed. After cleaning, the ECU also controls the air intake according to the original opening, and the engine idle speed will increase.

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