My car (pre facelift 8P S3) is doing some funny business when accelerating. With the throttle wide open, around when it hits boost (around 3000rpm), the revs climb very quickly for 400ish rpm and then drop again before the car proceeds to accelerate normally. There is definately no corresponding acceleration during this rev spike, in fact, it feels like its pulling less. Does not (seem to) happen if I gradually get up to higher revs and then open the throttle to accelerate (ie. no slippage if I open the throttle from 4500rpm)
This is most noticable in 3rd through 5th gear (usually not going fast enough for 6th) when there is load on the engine (uphill or flats for higher gears) and only occurs the first couple of times on wide open throttle each time the car is started after being off for a while. It happens both when the engine is fairly cold and the same if I've let it warm up completely driving it slowly. After those few times, acceleration is perfectly fine.
Car is GIAC'ed and otherwise stock. No warning lights, ESP on or off and I have new tyres (Eagle F1 Assym; which are amazing)... I've (already) done ~38000km and it was serviced at Audi at 15k and 30k.
Here are some videos of it happening... The audio makes it pretty obvious.
(shows it most obviously)
(normal acceleration, moments later)
Anyone know what's going on?