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I have a 1999 Mazda Familia which has a problematic speed sensor. I have already had it replaced but the problem of intermittent accelaration still occurs from time to time. Any suggestions? She's a wonderful car otherwise.

It would be interesting to know exactly how the speed sensor was originally diagnosed as being faulty and what steps have been taken to confirm it is playing up again.

Has anybody checked for fault codes in the engine management computer?