I had the Mechatronics unit, which controls the DSG transmission, replaced under the CPO warranty, because of very rough shifting under low speed conditions (when you'd by finessing the clutch and throttle with a manual transmission). It transformed the transmission from really cool to fantastic! Unfortunately, it would very expensive if it's not covered by a warranty of some kind. The awkward downshift when coming to a stop was one of the many improvements.
One cool thing on 2006 A3's is the ability to adjust the steering boost with a VAG-COM interface (the steering boost adjustment is not possible on later years). This interface and software work on a Windows laptop, and enables many very cool functions, but the steering adjustment is one of the best.
Other things I've done with VAG-COM:
- Enabled my fog lights as DRLs
- Calibrated the mpg function of the trip computer
- Enabled heated mirrors (my car did not have the cold weather package)
- Disabled the auto door locks
- Enabled the keyfob to close windows + sunroof, or open windows (no sunroof open option)
- Made some minor changes to the Bose radio settings
- Changed the timing for the seat belt warning light
- Performed boost and torque measurements (from which I calculated horepower). There's LOTS of measurement capability available with VAG-COM, including time-to-speed and distance.
- And best of all, I can read the diagnostics when I get a Check Engine Light.
The VAG-COM people are super helpful and very active over on this Fourtitude Forum:
http://forums.fourtitude.com/zeroforum?id=510
Here's an archive of VAG-COM threads to give you an idea of its many capabilities:
http://www.audi-sport.net/vb/archive....php/f-27.html
If you're interested in this, do yourself a huge favor and buy the real interface from them, not something cheap off ebay. (No, I do not work with or for Ross-Tech, I'm just a very satisfied customer.) Here's a link to the VAG-COM manufacturer:
http://www.ross-tech.com/