i have a 2006 audi a4 quattro 2.0T b7 body with 128,000 miles. mods are apr stage 2+ tune, downpipe, forge dv, awe front mount intercooler, newmotor boost gauge. the other night i was driving my car and in third gear at high rpms my boost would fluctuate i usually hold about 20psi and i was only getting 15 down to 10 back up to 15 back down to 10 . im not sure what the problem is but im very worried, if you have any ideas please let me know.

 

You get a CEL (check engine light)? even if you don't, see if you can get your hands on a vag-com or if u cant, go to autozone and get your car scanned to see if any codes pop out. I'd trace your boost lines to check for cracked/loose clamps, specifically your boost gauge tap, that could deff be the culprit.

 

its your hpfp going stage 2 + u will see fuel cuts that would drop your boost as well

 

well , the other day it was fluxing as i stated previously, and now in second gear it over boost hits 23 , and then it hit 24 and went into lymp mode , i heard it could be my n75 valve ? i dont have a cel, and i went to autozone , nothing .. my friend has vagcom im tryng to meet up with him . but i also heard that it could be my fuel filter , not pump. but the fuel pump is only 4 months old i dont get it