I have had the engine management light on my A2 1.6 for over a year and no mechanic or expert seems to know what to do. I had it scanned and the garage told me it was a problem only Audi could sort and they want £100 to scan. I bought the Vag free ware and did it myself and got codes 17439 (intake manifold tuning valve) and 17478 (NOx sensor heater control short to plus/open circuit). Any help would greatly recieved!!!!