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lou’s garage

A friend purchased a preowned 2014 Audi S4 [3.0-litre] from a dealership in June of 2015 and had it tuned in 2016 with 33,000 km on it. He brought it back to the dealership last week to have some warranty work done as he was having issues with the timing chain and tensioners. The dealer notified him that the computer system was showing the vehicle was flagged due to the modifications made and therefore would not be covered under warranty. He believes the tune has nothing to do with the work that is required. - Jennifer

The "tune" in question is an after-market reprogramming of the vehicle's onboard computer to increase engine output.

Your friend's supercharged Audi S4 likely received a noticeable performance gain of at least 25-35 horsepower from this tune.

Enthusiasts are eager to swap out their stock programming, viewing this software-only modification as "free horsepower" since no parts are required.

But is it free? Audi doesn't think so. Their design team calculates the final power output numbers with consideration to engine and drivetrain longevity. Any performance gain means increased wear to those components. How much wear and whether that additional horsepower caused the timing chain to fail is debatable, it is also virtually impossible to disprove.

Car enthusiasts now need to think twice, as any modification during their vehicle's warrantable period clearly has a risk associated with it.

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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