http://www.autoblog.com/2004/06/22/hyundai-settles-overstated-horsepower-lawsuit/Hyundai Motor America will be parting with $30 million in order to make up for the horsepower numbers it fudged over the past decade. Up to 858,000 Hyundai owners can get in on the class-action suit, which has been resolved with Hyundai offering debit cards worth $50 to $225 in regular currency or cards worth slightly more when used at Hyundai dealers. Power figures were off by almost 20-hp on a few V6 models, but many Hyundai owners saw a much smaller difference, for instance a so-called 140-hp Elantra packed a mere 136. 120,000 owners have already stepped forward and the final tally will most likely be close to 200,000, of which one or two may have actually taken horsepower into consideration before purchasing their Hyundai.
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http://consumeraffairs.com/news03/mazda_buyback.htmlSeptember 5, 2003
Mazda is offering to buy back all of the 2004-model RX-8 sports cars sold in the United States because the car's rotary engine produces 4.8 percent less horsepower than expected.
Customers who choose to keep their cars will get free maintenance for four years and $500 in parts and accessories, the company said. Letters went out to registered owners in late August.
Mazda initially said the manual-transmission RX-8 would produce 247 horsepower, the automatic version 207. But after making modifications to meet U.S. emission rules, the correct figures were 238 and 197, Mazda said.
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Those are just a couple examples. The same happened with Ford a few years ago. Just can't remember the details or find a link.
