15000 miles on my 01TT and recently I've noticed that when I kill the engine I hear 3-4 quick knocks in quick succession as the engine stops. The Porsche mechanic heard it and immediately said that it's my dual-mass flywheel. To prove it he had me kill the engine while the clutch was engaged... no knocking sound.

So he tells me it's quite common, especially on TT's and that it won't affect the performance or reliability of the car. My car is under warranty and he says he can replace the flywheel, which requires the removal of engine and transmission.

Can anyone verify this is a common issue w/ no side effects? And should I have the flywheel replaced? And if I have it replaced is there anything else I should do to my stock car while it's torn apart?

Your thoughts are appreciated.

David