There are a few known faults. Issues with the diesel particulate filter are common, so check and see if the car has had maintenance done on that. Blown turbos are also a common fault, so if throttle response seems sluggish, that could be the cause. The 1.9 TDI engine needs a cam belt change every 100,000km so make sure that’s been done. Exhaust gas recirculation valves can go faulty, and the signs will be an engine that’s rough at idle. DSG gearboxes can be troublesome if they haven't been serviced properly, while the front anti-roll bar bushes can deteriorate.