The 2009 Audi A3 has 3 recalls, the most serious being a driver's frontal airbag inflator that can rupture or explode during deployment, sending metal fragments into the cabin and potentially causing serious injury.
The airbag issue has been the subject of prior repair attempts that did not fully resolve the problem, so owners who had earlier work done should verify whether their vehicle still requires service. Separately from the airbag concern, the anti-lock brake system control unit can fail during ABS or electronic stability control activation, causing the driver to lose control of the vehicle at a moment when those systems are needed most.