Flyod: Sounds like the G62 temp sensor is borked and the ECU assumes that it is still cold out even when the engine is warm = running rich = smoke = poor mileage. Suggest you have a look in the AudiWorld UrS-car FAQ at: http://forums.audiworld.com/s4s6/msgs/150040.phtml Should help. I am not sure of the G62 part no. KATE is such a bitch sometimes. Dave F.