Is the fault problem of Volkswagen electronic throttle control system big or not?

Throttle, commonly known as throttle valve, is a controllable valve used to control the intake of engine. Causes of failure include carbon deposition in the throttle body, failure of the throttle in the fully closed position, failure of the throttle position actuator or its circuit or connector, failure of the throttle control module, misalignment of the accelerator pedal and failure of the electronic control module (PCM or ECM).

It is suggested that you need to replace the throttle assembly. Although it is a little expensive, it can solve the fundamental problem.