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Crankshaft Group - Setting crankshaft to TDC

15-242 Setting Crankshaft to TDC Flywheel timing mark

If the engine has been dismantled, it should be reassembled with both the crank and camshaft set to TDC - otherwise valve or cam damage is a possibility.
The small recessed mark on the flywheel resembles a figure "0" aligned along the car. It is sometimes VERY hard to see and a very small light (Aaron Bendalite Pro, single LED) providing diagonal illumination is useful. If the flywheel is removed, a small dab of white paint (or Tipp-Ex, Liquid Paper) on the mark can be useful.

13-799 The Harmonic Damper Mark

This is documented here for the sake of completeness and conformance with original Audi documentation. However experience has shown that the inner portion of the harmonic damper - forcibly aligned with the crankshaft via the Woodruff Key - can and does move relative to the outer portion over the life of an engine. The mark on the outer rim of the harmonic damper pulley is reliable only on a new harmonic damper - if the engine has EVER run, the flywheel mark must be used as it is definitive.