Hawaii auto sales fell sharply in the third quarter, prompting the Hawaii Auto Dealers Association to project a decline in 2011 sales to the lowest level on record.

Dealers statewide sold 7,909 cars and light trucks during the July-through-September period, 15.1 percent fewer than the same stretch a year earlier, HADA said Wednesday in its quarterly Hawaii Auto Outlook.

As a result of the decline, HADA revised its full-year sales forecast down to 33,500 autos, which would be the lowest annual total since the trade group began keeping records in 1989.

HADA attributed part of the third-quarter decline in sales to an unexpected continuation of supply disruptions from Japan, where a devastating earthquake and tsunami in March triggered factory closures that reduced auto production and exports. Japanese brands accounted for 65 percent of Hawaii’s auto sales last year compared with 42 percent nationally.

"The numbers show how vulnerable Hawaii’s recovering new car retail sales market is to events that happen in other parts of the world, like the Fukushima earthquake," said Dave Rolf, HADA executive director.

In the last Hawaii Auto Outlook, published in July, HADA forecast a 4.2 percent rise in auto sales to 35,448 in 2011. After release of the third-quarter numbers, HADA revised lower this year’s sales forecast, which would be a drop of 1.5 percent from 2010.

Auto sales for the past three years have been running at about half the record 70,000 sales reached in 2005.

The dealers’ group is forecasting a 10 percent rebound next year, as consumers satisfy their pent-up demand for Japanese vehicles and others get back into the market after having postponed new car purchases during the economic downturn.

"The light at the end of the tunnel seems to be the double-digit increase forecast for 2012," Rolf said.

Tom Griffin, president of Honolulu Ford, said he’s noticed a pickup in business during the past 10 to 12 days that he hopes will continue to build.

"Sales are coming up, not as fast at we’d like, but it is getting better," he said. "We’re looking for a much-better fourth quarter."

Griffin said he’s noticed that people are driving their cars a lot longer than they did before the recession hit in 2007. New car buyers used to bring their old vehicles in for trade-in after two to three years, he said. That increased to three to four years as the economy began to slow, and by the depths of the recession his dealership was seeing buyers who waited more than 10 years to trade in their old cars.

"Now we’re beginning to see that turn around," he said.

Kenny Ching, general manager for Pflueger Honda, said shipments from Japan are finally at levels that existed before the supply disruptions.

"Things are getting better," Ching said. "We’re upbeat about that. Those issues are behind us and we are moving forward."

The recent slump in auto sales has hit Hawaii harder than the mainland. While Hawaii dealers struggled to eke out a 1.1 percent increase in sales last year, the rise nationally was 7 percent. Hawaii’s forecast for a 1.5 percent decline compares with a projected 10 percent increase for the nation as a whole.

Rick Ching, president of Servco Automotive, said, "We anticipate fairly robust sales through the end of the year and into the first quarter of 2012."

One bright spot for Hawaii has been on Maui. Auto sales there have bucked the statewide trend, rising 5.9 percent for the first nine months of the year from the same period a year earlier. For the same period, sales were down 6.3 percent on Oahu, 2.9 percent on Kauai and 2.8 percent on Hawaii island.