Hi Ive had my a3 1.8t (1997)for a few months now, everything was fine but over time i noticed my boost was on and off, now its pretty much gone? ive fitted a boost gauge and its always on 0.3 ( one morning the turbo boosted fine for ten mins and went well over that) Ive checked and changed hoses,dump valve,done all the common checks etc but still no luck.
My mechanic has plugged it up to find any fault codes, the only one it has is throttle body sensor faults, would a broken throttle body sensor effect my boost?

cheers