Quote Originally Posted by two2 View Post
from where do you access the orifice tube, does the bumper need to be removed? part number for o-rings? thanks.
The orifice tube is within, one of the two alum A/C lines - up top, in the engine compartment. No need to take off the bumper cover. You will need to take out the full width, plastic cover, (where the battery and brake master cylinder and reservior are located - carefully, it's slid into a grooved plastic piece by the windshield and tcuked under the rubber strip that seals this area from engine compartment. To: get to the second schrader valve...

O-rings - there are MANY and each has a part number - go to Audi Part USA - print off the exploded parts diagrams, then the follow pages, with the part numbers - diligence is required!

WB