Hi, i'm new here and also a new owner.
I had my (used) A3 for 2 weeks and the turbo blew. I got it from an Audi Approved dealer.
They replaced the turbo unit (under warranty, phew) and all was well until this weekend. I had it doing 80mph in 6th and was fine, but over 80mph there was a loud vibration from the front of the car. when i slowed down, it went.
It didnt appear to be rev-related as when i stuck it in a lower gear and hit 3000rpm, (more than i was pulling at 85mph in 6th) there was no noise.
I was also aware that my engine was quite noisey under acceleration - the whooshing sound from the turbo seemed loud but maybe this is because its meant to and my old one was broken so it isnt a good comparison.
Performance seems OK too, decent power all the way up. There was no change in performance when the vibration occurred.
I did notice that when idling, the engine block seems to move around quite a bit in the engine bay, and i can feel this when sitting in traffic sometimes. The main dealer saw this when i took it in to get the turbo replaced and they said the broken turbo was making it jiggle about. Now its fixed, its still jiggling!!
any ideas as to what might be the problem?