Audi S8 D2 misfire Lambda sensor fault

[H24k]

My 1999 facelift 40v Audi S8 has a serious misfire which is very noticable at tick over and the car shakes quiet violently! Ive changed spark plugs, Coil packs, checked injectors etc etc and still the same however the car recently threw up some fault codes one of which is 16534 Check Oxygen (Lambda) Sensor Heating Bank 2 Sensor 1, found the info here http://wiki.ross-tech.com/wiki/index...ible_Solutions

Just wondered if anyone knows where this actual sensor is located so I can change it to see if its the cause of the misfire, my car is a UK right hand drive, Thanks