Friend had the same fault, 1 vauxhall dealer couldn't find anything wrong. Took it to another dealer and they informed him that the car had not been put together correctly and it need to be rewelded along the seam between the roof and the side panel around the rear quarter light. Fortunately for him the car was still covered by the Vauxhall warranty. Best to get it checked out.
Uncle
April 2005
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