Do I have a case against a garage misdiagnosing a fault?

I took my 2013 Volkswagen Passat into an independent Volkswagen garage because the washer jets had stopped working. I told them that the motor was not making any sound at all. After nearly two hours they hadn't found anything obviously wrong but I was charged £78.20 plus vat (£93.84)! I decided to take it to my local Halfords and they immediately diagnosed it as the motor/pump not working. I have been in touch with the first garage and told them of their mis-diagnosis, but they say they have done nothing wrong! I feel that I have been overcharged for something that they did not put right. Do I have a case against the garage?
This is a lesson never to darken the doors of that incompetent, rip-off Volkswagen dealer ever again. But not worth suing them for £93.84.
Answered by Honest John on

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