EPC light on dashboard, car sometimes cuts off

This will happens when either the throttle body or accelerator pedal needs to be replaced, it is difficult to tell which one this is why the dealer will replaced both. I would service the throttle actuator first o see if that helps and it is the cheapest thing to do.

Here is a generic guide to help you step by step with instructions in the diagrams below to show you how on your car. Here is more information about the problem.

The Electronic Power Control (EPC) light in a vehicle like the 2009 Audi Q5 typically indicates a problem with the engine's electronic throttle control system. When this light comes on, it means that the vehicle's onboard computer has detected a fault or malfunction in the system, and it may limit the engine's power output to prevent further damage.

Here are some common reasons why the EPC light may come on in an Audi Q5:

Throttle Body Issues: The throttle body is responsible for controlling the amount of air that enters the engine. If it becomes dirty, clogged, or malfunctions, it can trigger the EPC light.

Mass Airflow Sensor (MAF) Failure: The MAF sensor measures the amount of air entering the engine and helps the engine control module (ECM) adjust the air-fuel mixture. A faulty MAF sensor can lead to EPC light activation.

Accelerator Pedal Sensor: Problems with the accelerator pedal position sensor or its wiring can lead to issues with the throttle control system and trigger the EPC light.

Check out the images (below). Please let us know how it goes.