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lou’s garage

Our Ford Fusion recently developed a jerking motion. Our Ford dealer tested it but could not find anything wrong. After a long trip we returned to the same dealer, and this time, the problem was detected and the faulty purge valve was replaced.

Could any experienced technician have found a solution from our initial description, or are we expecting too much from a human being now that computers have taken over the workplace? - Elaine

With the absence of any dashboard warning indicators, I will assume that your vehicle's Powertrain Control Module (PCM) failed to detect a problem and no data was stored in the PCM's memory. Attempting to replicate the problem during a test drive would be the technician's next logical step. If the test drive still produced a no-fault-found condition, then little could have been done through traditional diagnostic avenues.

An independent repair facility may be willing to work with your description only and offer a common or "most likely" repair solution, but the dealer experience will often dictate a different procedure. Firstly, speculating does not generate any diagnostic labour revenue for them, and if they guess and they are wrong, the customer will return unhappy. It is reasonable to think that the first technician had a hunch of what was ailing the vehicle but didn't act upon it because there was no supporting data. Situations like these are common, as human involvement is still key at all levels in the automotive service business.

Lou Trottier is owner-operator of All About Imports in Mississauga. Have a question about maintenance and repair? E-mail globedrive@globeandmail.com, placing "Lou's Garage" in the subject area.

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