I get this in my 2008 A4 only when we hit the coldest days in the winter, EPC light comes on and i get no response from the throttle pedal and sometimes a P2101 code until the engine warms up the bay or interior. Figured it's condensation freezing up in a sensor or connector for the pedal or throttle body but i've cleaned and used di-electric grease in any associated connectors. Was going to seal up the ECU cover too, but i keep forgetting about this till i'm stuck on the side of the street waiting for heat.

https://www.google.com/search?q=audi...hrome&ie=UTF-8

^Some direction to other EPC issues.