NEW YORK - Ford, General Motors, and Chrysler have made strides in new-vehicle quality over the last year but remain behind their foreign competitors, according to a closely watched study released yesterday by J.D. Power & Associates.

The initial quality of 2009 model-year vehicles sold by the Detroit Three improved by an average of 10 percent from last year, J.D. Power said. That beat the average industrywide improvement 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," David Sargent, vice president of automotive research at J.D. Power, said in a statement.

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

J.D. Power credited the improvement to several well-received new models launched in 2009. Several redesigned 2009 models also scored well, the marketing and consulting firm said.

Lexus, Toyota Motor Corp.'s luxury line, was the top brand in J.D. Power's 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.

The worst-performing brand was Mini, which is made in Britain and includes the Mini Cooper, with owners reporting 165 problems per 100 vehicles.

Although Chrysler's scores improved from last year, it had no brands above the industry average.

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 Chevrolet and Cadillac accounted for 70 percent of GM's volume, and top marks for those segments are a key sign of the company's effort to improve quality.

Ford Motor Co., the only major U.S. automaker that has not filed for bankruptcy protection or accepted government aid, also saw its J.D. Power 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.

Top Models

Highest-ranked vehicles

in selected categories:

Compact car:

Hyundai Elantra sedan.

Compact sporty premium car: Nissan Z.

Midsize car:

Nissan Altima.

Midsize premium car:

Lexus GS.

Large car:

Mercury Sable.

Large premium car:

Lexus LS.

Midsize activity vehicle: Chevrolet Trailblazer, Ford Edge, Toyota 4Runner (tie).

Midsize pickup:

Honda Ridgeline.

Van: Toyota Sienna

SOURCE: Associated PressEndText