Replace throttle wire harness.

There are many reasons why the EPC light of Audi A4 is on (many small partners have basically responded to this question, which can be said to be a common problem), such as:

1, oil problem. It is possible that inferior gasoline was added.

2. Because the throttle body is dirty, this situation can be solved by cleaning the throttle body and matching it again.

3. If the sideslip light comes on at the same time and the car feels dead, especially the acceleration is weak, it is necessary to replace the "accelerator harness" connector, that is, cut the original wires and reconnect them in the order of wires.

4. There is a leak in the air intake system, which affects the engine adjustment unit to light the EPC warning light after checking the problem.

5. There is leakage in the crankcase ventilation system.

6. If the brake light is not on, check the brake switch and circuit.

It is recommended to go to a 4S shop or a professional auto repair shop, and let the mechanic connect to the computer, check the fault code and solve it according to the specific reasons.

Attached with EPC lamp description:

EPC=ElectronicPowerControl (full name of engine electronic stability system) is also called electronic throttle by many people. The system consists of point sensors, regulators and other components. When the sensor fails or senses an abnormal situation, the regulating system will take corresponding measures according to the set procedure.