Hi all I have a 2004 A3 2.0Tdi 3dr. It has gone into limp mode twice this week, so I took it to an audi specilist to have it looked at. It threw a code 16683 P0299 It has only gone into limp mode when i am sitting at around 70mph, with no load on the engine what so ever. Has anyone else ever had this happen to them?? Also do the turbos have variable vein geomerty?? If any out there is in the know, please can you fill me in. Thanks A!