Ford, General Motors and Chrysler have made strides in new vehicle quality over the last year, but they still lag behind their foreign competitors, according to a closely watched study released Monday by J.D. Power and Associates.

The initial quality of 2009 model year vehicles sold by the Detroit Three improved by an average of 10 percent from last year, the marketing and consulting company said. Industrywide, scores improved an average of 8 percent.

"The Detroit automakers are keeping their focus on designing and building high-quality vehicles, which is a precondition for long-term success," said David Sargent, vice president of automotive research at J.D. Power, in a statement.

Lexus, Toyota Motor Corp.'s luxury line, was the top brand in J.D. Power's initial quality study, an annual survey of vehicle owners that measures mechanical and design problems in the first 90 days of ownership.

Porsche was the No. 2 brand, followed by GM's Cadillac, then Hyundai and Honda.

Toyota, which supplanted General Motors Corp. as the world's largest automaker last year, also swept 10 vehicle segment awards. Its assembly facility in Higashi-Fuji, Japan, that builds the Lexus SC 430 and the Toyota Corolla took the J.D. Power's top plant award.

The worst-performing brand was Mini, with owners reporting 165 problems per 100 vehicles. Though Chrysler's scores improved year over year, it had no brands above the industry average. It tied for one segment award, with its PT Cruiser Wagon sharing the top award in the compact activity vehicle segment with Honda's CR-V. Chrysler, however, is discontinuing the car.

Cadillac and Chevrolet were GM's only two brands whose 2009 models performed above average. The four brands GM is purging under Chapter 11 bankruptcy protection — Pontiac, Saturn, Hummer and Saab — were the company's worst rated. The Chevrolet TrailBlazer and GMC Yukon SUVs were rated best in their segments.

Jamie Hresko, GM's vice president for global quality, said the automaker has worked hard to improve vehicle quality over the last five years. Chevrolet and Cadillac account for 70 percent of GM's volume, he said, and top marks for those segments are an indication the effort is paying off.

"Is it where we need to be? No," Hresko said. "To have our core brands — Cadillac and Chevrolet — be on par with Toyota, we have reached a level of quality that will allow us to change perceptions."

Ford Motor Co., the only major U.S. automaker that has not filed for bankruptcy protection or accepted government aid, also saw scores improve for three of its four brands: Ford, Mercury and Volvo. But its Lincoln brand's score fell, and only Ford and Mercury performed above the industry average.

The average industry score improved to 108 problems per 100 vehicles, down from 118 in 2008.

J.D. Power credited the improvement to several well-received new models that were launched in 2009. It said vehicles like Hyundai's Genesis, Kia's Borrego, Toyota's Venza and Volkswagen's CC performed better than their segment averages. Several redesigned 2009 models also scored well, J.D. Power said.

The scores come during a tumultuous time for the auto industry, with sales at their worst level in decades and taxpayers stuck funding the restructuring of GM and Chrysler Group LLC to the tune of billions of dollars. Although the two automakers have been pummeled by the economic crisis, many analysts have complained that a shortage of high-quality small car offerings has hobbled their performance in the down market.

GM has several new, small vehicles on the way that industry analysts say should help it better compete with established offerings from Toyota, Honda and other foreign competitors. It plans to start building the subcompact Chevrolet Cruze next year and says it will get about 40 miles per gallon. It also plans to sell the Chevrolet Spark minicar in the U.S. in 2011.

The road may be tougher for Chrysler. Cars like the sporty 500 made by its new owner, Italy's Fiat Group SpA, won't make it to the U.S. until late next year. The Auburn Hills, Mich., company plans to roll out new versions of its popular Jeep Grand Cherokee SUV and Chrysler 300 large sedan by the end of next year, along with a rechargeable electric vehicle, but these plans likely have been delayed by the bankruptcy process.

J.D. Power's rankings were based on questionnaires from 80,900 people who bought or leased new 2009 vehicles between February and May. The questionnaires ask 228 questions on issues from handling, braking and engine trouble, to seat comfort and stereo systems.

The rankings are closely watched by automakers and consumers, and are frequently used in advertising. However, some critics question whether they show any real statistical difference between automakers. Mini's ranking, for example, equates to 1.65 problems per vehicle. Top-performer Lexus had 84 problems per 100 vehicles, or 0.84 per vehicle. So on average, less than one problem per vehicle separates the best brand from the worst.

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