Timing belt replacement

For what liter engine?

You gonna be needing special tools and a repair manual if you haven't done such a thing I suggest you take it a shop

CAUTION:When turning camshaft, crankshaft must not be at TDC, or there is a potential for valves to contact pistons. Install timing belt when engine is cold or lukewarm.

Align timing marks on camshaft sprocket with mark on cylinder head cover. Ensure crankshaft sprocket is still aligned with timing mark.
Install timing belt around crankshaft sprocket. Install lower timing belt cover. Install NEW vibration damper bolts, and tighten to specification. See TORQUE SPECIFICATIONS.
Set crankshaft pulley to TDC No. 1 cylinder. Place timing belt on water pump, tensioner pulley and camshaft sprocket. For models built through July 2000, go to next step. For models built after July 2000, go to step 5.
NOTE:Engine must be cool (not more than lukewarm) when tensioning timing belt.

On models built through July 2000, remove Locking Pin (T40011) and unscrew Tensioning Bolt (T10092). See Fig. 7.
CAUTION:If tensioner is fully extended at any time, it must be pressed back into compressed position using tensioner assembly and Pin Wrench. Excessive force during this compression procedure can damage tensioner assembly.

On models built after July 2000, rotate tensioner counterclockwise using Pin Wrench (3387), removing all tension until Locking Plate (T10008) can be removed without force. After removing Locking Plate, rotate tensioner clockwise using Pin Wrench until a 5/16" (8 mm) drill bit can be inserted between tensioner lever and housing through underside of tensioner. While holding tensioner in this position, tighten tensioner retaining bolt to specification. See TORQUE SPECIFICATIONS.
On all models, turn crankshaft 2 revolutions in normal direction of rotation. Check that camshaft and crankshaft timing marks align properly.
On models built after July 2000, using a drill bit check dimension between tightening lever and housing of tightening device. Specified value.236-.393" (6-10 mm). If dimension is not as specified, repeat timing belt tensioning procedure.
To finish installation, reverse remaining removal procedure. Tighten all fasteners to specification.

Fun job... here's a link with videos:

http://www.passatworld.com/forums/42-volkswagen-passat-b5-discussion/346909-excellent-timing-belt-video-tutorial.html

Thomas

I changed one on a 1.8T New Beetle today. A lot less room.

You don't have to pull the whole front end off of your car. Just
pull the bumper off and pull the radiator carrier forward into the
service position (12" or so).

Thomas