loss of power - A4 S Line T Fsi Quattro A

[robips]

New here and seeking advice. Im not a mechanic either so please forgive my descriptions,

When accelerating hard from around 60, car wont rev over 3000rpm or accelerate (guess like limp mode), it does seem to reset itself quite quickly but not good if i'm overtaking and lose power. Any suggestions as to what may be causing the issue?

My general mechanic is stumped, and car is only throwing up minor Intermittent codes which he says are not related.

grateful for any input.