I ran in to a similar question when I was servicing my younger brother's Audi A4. The owner's handbook was not very helpful when identifying spark plugs or transmission and differential fluids that were readily available. Everything said see dealer for current recommendations. I dislike Bosch Platinum, and Autolite plugs,I like NGK, and Denso. Advanced Auto probably have the correct
I would urge you to use the dealer supplied genuine part. Usually manufactured by NGK or Beru. Various issues related to cold start/performance and misfires are related to aftermarket spark plugs. This statement is based on years of experience.
http://www.a4mods.com/index.php?page=webcontent/pages/copperplugs.html&category=1 follow this link these guys know what they are talking about. I use the NGK spark plugs like they do and have had great success!