Audi A4 S-line Avant 2.0T FSI
Its a bumper off job and its a right pain to do and i do bodywork for a living!
You need to undo and drop down the wheel arch liner to get to another set of bolts that hold the bumper on which are rather high up inside and akward to get at. Obviously both sides.
Then you need to remove the interior panels in the boot to get at just below the inside of the rear light cluster. Two bolts which are again a pain to get to. If you have BOSE then this needs removing aswell to get at the bolts on the drivers side rear.
Bolts along the slam panel and then some more underneath.
Once the bumper is off its a case of releasing the wiring and unclipping the parking sensors.
Im not sure about the cleaning of the sensors as i would fitted new ones to mine.
If this is too big a job then i would go to a bodyshop and pay an hours labour or cash to get someone to remove the bumper. Its not a hard job just a pain and alot of scrapped knuckles!
If it's got t*ts or wheels, it's TROUBLE!