(DETROIT – Korean automaker Hyundai Motor America, which struggled with its quality reputation only a few years ago, has leapfrogged Detroit’s automakers and is now ranked just below perennial leader Toyota in a closely watched survey of new-vehicle quality.

Hyundai tied Honda Motor Co. for second place, and it surpassed European rivals in the J.D. Power and Associates Initial Quality Survey, released this week.

Toyota Motor Sales, which includes the top-rated Lexus brand, as well as Scion, took first place in companywide initial quality, however the Hyundai brand outperformed the flagship Toyota brand.

Detroit’s automakers, though improved from last year, all ranked below the industry average.

J.D. Power surveyed more than 51,000 people three months after they bought or leased a new vehicle, asking about more than 100 potential problems.

Hyundai, which used to rank near the bottom of the study, made a vast improvement from a year ago, going from 143 problems reported per 100 vehicles to 102 problems. The company attributes the improvement to a years-long commitment to advancing its quality. In the 1999 model year, the company began putting a 10-year, 100,000-mile warranty on its vehicles as an assurance that it had changed.

Toyota had 101 reported problems, compared to 115 in 2003.

Hyundai said it knew it had made dramatic quality strides in recent years, but it had no idea that it had come this far.

“We are all over the moon with happiness,” said Chris Hosford, a spokesman for Hyundai. “We knew this was coming,” but “very few of us knew that we would make this big of an improvement.”

Hyundai soured Americans during the 1980s largely because of its small, poor-quality cars. But the warranty, along with better styling, has helped the automaker gain market share.

“They’re doing a better job of understanding the U.S. consumer,” said Brian Walters, J.D. Power’s senior director of vehicle research. They know “what they like and what they don’t like.”

General Motors Corp., the highest-ranked domestic automaker, improved its quality score by 10 percent to 120 complaints per 100 vehicles. But it still came in just behind the industry average of 119 problems.

Gary Cowger, president of GM North America, said the automaker performed well given that it launched 13 new products last year.

Typically, new-model launches or midcycle improvements cause a 5 percent uptick in problems, which are then reversed the following year, J.D. Power has said.

Hyundai didn’t launch any new vehicles last year, which likely helped the automaker, J.D. Power said. Still, Hyundai contends that it is one of the few companies that can launch new models that have fewer problems than the old ones.

Ford also improved its score 7 percent from a year ago, the study said, but its overall ranking slipped from a year ago, falling behind both DaimlerChrysler and Subaru.

Ford also said it was pleased with its performance. Louise Goeser, Ford’s vice president of quality, said the company was up against a tough challenge with the launch of the F-150 last year.

DaimlerChrysler had 123 complaints per 100 vehicles, 16 fewer than last year.

The industry average for initial quality improved from 2003, going from 133 complaints per 100 vehicles to 119 complaints.

The number of complaints consumers have about their vehicles is lower than it was 18 years ago, when the firm released its first Initial Quality Survey. Back then, automakers were plagued with far more serious issues, ranging from electrical problems to vehicles that just wouldn’t start.

These days, vehicle owners complain about wind noise and worse-than-expected fuel economy, especially in light of rising fuel prices. Like last year, both problems ranked high on the list of the things that bugged consumers the most about their vehicles in the first few months.

Poor fuel economy was a common complaint for Hummer sport-utility vehicles, which had the highest number of complaints of any brand.