Mil light comes on after about a month after deleted, fault code P1297(connection turbo/throttle valve, P1137 Fuel trim bank 1 ADD system to rich) I see a post in January 2009 with same codes,on audi A3, did you cure it ?,I have done smoke preesure test, slight loss from oil dip stick, have replaced diverter valve, vehicle drives fine, no complaint from customer,no fault at time of testing.