I've just had my 2007 S3 remapped using Bluefin and taken it on its first run out. Whilst the boost in power (and the way it's delivered) is great, I do have a problem....
On full throttle, the car behaves as though it is being restrained, with power delivery smooth for a second then dropping off as the engine revs, then comes back as it should. This is a accompanied by a 'squirrelling' sound from under the bonnet which I've never heard before.
My first thought is this is being caused by the factory fit wastegate which may need replacing? I had a similiar but much worse problem when I had my Mk5 Golf Gti remapped and replacing the wastegate solved it. My S3 is 4 years old with 45k miles on the clock, and I know the standard wastegate isn't built to last, so this is my initial thought as to what the problem could be.
Before I spend my hard-earned on a replacement, has anyone else experienced a similar problem and have a suggestion as to what the cause may be?