The hardest problem to find is the one that you assume is not a problem. I have seen many a technician become stumped simply because a new distributor rotor failed.
No it is not a common thing. It is possible if some one did not properly tighten that bolt down on most vehicles not just VW or Audi. And I like to use locktite on that bolt to keep it tight! ;-)
later, dave (One out of many daves)
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