Just got myself an A3 1.8TS On a 97 (R) Palte.

Had it a week now and in test drive the car seemed fine. Must admit didnt really give it much stick!
First gear sometimes seems really shakey? it has 18's so i was thinking maybe it was that. but after reading some posts not too sure now!
Also when i put my foot down in second the turbo kicks in then seems to die out then kick in then die out and so on...this doesnt happen everytime just Irregularly. It also seems alright in all the other gears.
I have done a bit of reading on here but still a little worried!

Can anyone help or give me some advice please? Thanks...