See Figures 1 and 2
Volkswagen does not specify an inspection or replacement interval for timing belts. However, since some engines utilize an interference design, it is highly recommended to inspect the timing belt at 60,000 mile (96,000 km) intervals (especially on diesels). It is an even better idea to replace the belt at these intervals. It is far less expensive to replace the belt than to repair the engine damage which could result from the belt breaking.
Inspect the belt for cracks, missing teeth and wear on any of the surfaces. Inspect the sprockets for grease and other deposits. If any of these conditions exist, the belt should be replaced. Please refer to Engine & Engine Overhaul for procedures on timing belt removal and installation.