I know it's not a diesel, but as you know, there are experts here!
Today, for the first time, I used VAGCOM to check the error memory of my A6 (two weeks old), with engine code ASN, as a preventative measure. So far, I haven't noticed any errors while driving.
VAGCOM reports:
18010 - Control unit defective.
002 - Lower limit exceeded - Intermittent.