Bit late coming to this one, but my 2010 Astra does it too. I think ive read its a moderately common problem. TBH it doesnt cause me any problems. There may well be a fix, but ive happily run mine for months, its a bit of a distraction, no more.. In my case its not clutch slip.
colin
November 2013
sounds like your clutch is slipping.If it is then its a g/box out job.
cdc
October 2013
It's an manual
Steve
October 2013
Is it auto or manuel. Over revs when changing gears
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