Toyota Motor Corp. (TM) continued to dominate the initial quality rankings, grabbing the top spot in 11 out of 19 segments in the 2006 survey by J.D. Power and Associates, released Wednesday.

Porsche dominated the overall ranking of brands, averaging 91 problems per 100 vehicles. That compared with an industry average of 124 problems per 100 vehicles.

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The study, in its 20th year, was revamped to isolate consumers' concerns about design flaws, as distinct from defects and malfunctions. The change in methodology makes year-to-year comparisons impossible.

However, a parallel survey conducted using the old methodology found that as a whole, the industry improved 8 percent from 2005, said Joe Ivers, executive director of quality and customer satisfaction research at J.D. Power.

Lexus, Toyota's luxury brand, came in second in the overall nameplate rankings, with 93 problems per 100 vehicles. The Toyota brand came in fourth with 106.

"They're the closest thing to defect-free," Ivers said of the two brands.

In vehicle segments, Toyota had five winners, including the Corolla for compact car, the Camry for midsize car, and the Sequoia for large sport utility vehicle. Lexus had six top vehicles, including the IS 250 and IS 350 for entry premium car, the SC 430 for premium sporty car and LX 470 for large premium SUV.

Of the Big Three domestic automakers, General Motors Corp. (GM) made the strongest showing. Its vehicles won in two segments — large pickup (Chevrolet Silverado) and large car (Pontiac Grand Prix). The Chrysler Town & Country was the top-ranked van, and the Ford Ranger won for midsize pickup.

Hyundai Motor Co. scored a sleeper hit with consumers, with the Hyundai brand coming in No. 3 with an average 102 problems. The Hyundai Tucson took the top spot for compact SUV or crossover.

For the study, J.D. Power collected responses from 63,607 purchasers and lessees of new 2006 model-year vehicles after 90 days of ownership.

This year's survey included 217 questions, up from 135 in previous years, and asked for information specifically about design problems, as well as defects.

BMW AG's BMW brand had few defects, but one of the highest number of complaints about design — specifically about the way the brand integrated new technology into its vehicles, Ivers said.

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