Quote Originally Posted by Avus RS4 View Post
Assuming that there is a temporarily stuck flap shaft and a malfunctioning the the flap position sensor, how hard is to replace the flap sensor and/or the flap shaft?
Educate me here as I want to learn more before taking it to a shop.
Also, would this involve removing the intake?
Because if that's the case I may have then do the intake carbon clean and inspect and diagnose the flap sensors.
I haven't retrieved my error codes, will do that tomorrow, but I have an EPC light and the symbol that looks like a catalytic converter turned on the dash screen
The intake manifold has to be removed to access the position sensors and the flap shaft. Your flap shafts are not going to need replacement, but there may be carbon buildup preventing them from turning properly. I would definitely wait until carbon clean time because of overlapping labor.

If you have vagcom, do the test detailed here, takes 5 minutes and you will know if the flap shafts have full range of motion: http://forum.rs246.com/viewtopic.php?t=77235
I would do the test once while the car is cold and once while it's at full operating temp.

If the arms appear to be moving fully on both sides, then one or both of your sensors will probably be the issue. The DTCs pulled will tell you which bank.