I bought the car at the end of may 2015 and absolutely love it but... The last couple of times I have driven it it feels like it's been missing or slipping between gears. More pronounced on uphils and usually less than 2500 rpm. I brought it in and when scanned the mechanic said that fuel bank 1&2 were both reading lean and they also got a code for the purge valve. I replace the purge valve with no change. CEL has not come back on yet. I have driven 25 miles or so over 5 trips sence they cleared the codes. As a newcomer to Audi I am looking for advise on how to properly proceed. Thank you everyone.