What usually happens, is that a chain rail (plastic guide - see pic in partsshop/fastlane) gets brittle with age, and breaks (especially if there is chain slap). The little plastic pieces get inbetween the gear and chain, and mess everything up.

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It is a truism that almost any sect, cult, or religion will legislate its creed into law if it acquires the political power to do so. Robert A. Heinlein


09 Jetta TDI
1985 300D