Why is my Ford Focus losing power?

My Ford Focus Zetec has recently started losing power whilst I am driving and the speedometer drops to zero. The car still moves but is very slow, and then after a few seconds the speedo jumps back up and the power kicks in. I have taken it to a garage but he said could be one of a few things. Any ideas what this could be??

Asked on 20 July 2010 by boo87

Answered by Alan Ross
It's a problem with the speed sensor in the final drive that the affects the way the car runs. The oil seals fail. Costs about £100 to replace.
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