Surging and erratic boost

[Eric Huppert]

Would remove and check the Intercooler to Intake (MM) hose very carefully.
Check the ribs in the bottom of the hose and check for seam splits.
Increased boost and old oe hose = vacuum and boost leaks. Engine movement
sometimes causes intermittent problems with this hose, will gradually
worsen.

Quick indicator is any oil or grime on the hose....

As far as pulling codes... If check engine light is present in dash it only
requires a jumper wire. If not you'll need to pull right side of dash out
and insert a check engine bulb. In a pinch you can swap in the seatbelt or
door ajar bulb. Check out Scott Mockry's site for detailed info. If you get
a overboost code it's probably the mm hose.

http://www.sjmautotechnik.com/

Run the codes, it will tell you if something obvious (or not) is wrong


Could be numerous other things, but the mm hoses are prone to failure,
especially with increased boost. Would suggest a set of SAMCO's. New hose
from Audi lists for 140, Samco set is available for apx 185 plus clamp
replacement. Sure that hose is available for less, (Mockry or Blau) but why
put the lesser hose on at even half the price of the Samcos?

Eric