The most significant mechanical differences for 2009 lie in the long-overdue addition of extra drivetrain options. Most notable is the availability of quattro all-wheel drive combined with the venerable 2.0-liter turbocharged engine. As before, Audi’s impressive dual-clutch transmission (dubbed S tronic) is optional on the 2.0-liter, but is now standard when you check the box for the larger 3.2-liter engine.
On the outside, the A3 receives a subtle yet reasonably effective face-lift, and includes the addition of Audi’s now-signature LED running lights in the headlight clusters. Although the overall length remains the same as in 2008, the reduced front overhang makes for a sportier stance, as does the slightly reworked front fascia. Rounding out the changes are smaller details such as redesigned door handles, mirrors and taillights.
Source: MSN Autos