have a 1999 A3 1.8t quattro and recently it not been running right
every time i am on higher gears (3dr+) around 3000rpm-4000rpm car starts juddering and a loss of power and when car warms up car does not seem to boost past 0.5 bar if you try there is no power and car just judders
i have had the coilpacks replaced and the MAF which i new were common faults with the 1.8t engines still did not fix the problem also did resiliance test on N75 valve showed 31.5 ohms so put it on the diagnostics and 2 faults showed up
01324 control module for all wheel drive (j492)
01312 powertrain data bus 37-00 faulty
which i thought should not cause my loss of power
any help would be grateful

cheers