What is the reason why the Volkswagen fault light and epc light are on at the same time?

The electronic throttle is dirty and should be cleaned.

In vehicle maintenance, faults indicated by epc lights are common. If the light is on, it indicates that the electronic throttle system may be faulty, which may affect the normal use of the vehicle.

Epc light is on. If the vehicle has no obvious fault, the vehicle can continue driving, and the driver can try to turn off the engine and restart the epc light. Even if there is no fault, the driver can't take it lightly, and the vehicle needs to be repaired and tested in time.

Extended data:

Precautions:

1, cleaning agents are usually very corrosive, which easily corrode aprons or oil seals, leading to unstable idle speed.

2. Don't over-clean: Over-cleaning the throttle will lead to premature scrapping of the throttle. The throttle will not be broken because of dirt, but it will die because of frequent cleaning, which will reduce the accuracy.

3. If the throttle valve is not initialized after cleaning, the work of the electronic control unit and the idle speed control element will be uncoordinated, which is characterized by inaccurate and unstable idle speed control, such as high and low idle speed.

4. When the engine is working, it is impossible to make the valve without any leakage. The leaked oil and gas will condense on the throttle valve with the colloid in the fuel, or condense on the throttle valve in reverse.

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