coil packs are instead of spark plugs. Audi share engines with other VW group cars, VW, Seat and Skoda so in the beginning all VAG makes were affected.
It may be that some unburnt fuel has affected the lamda sensor, I'd go and get a diagnosis done asap. It could be worth checking but if your A2 is under 5 years old you might be covered by the extended warranty for coil packs. Know this is the case for 1,6fsi's but not sure about 1,4's. In any case the cost has tumbled in recent years and the newer versions are reliable.