Industrywide sales probably fell at the steepest rate of 2008. They declined for the 11th month in a row, the longest slide in 17 years, as the financial crisis caused lenders to toughen loan standards and consumers curbed spending. Sales had dropped 11 percent through August, in part on high fuel prices, hurting U.S. automakers more than their Asia-based competitors. “It’s a credit story industrywide,’’ said Tom Libby, an analyst at marketing-research firm J.D. Power & Associates in Troy, Michigan. “Also, there is a psychological impact of all the news about banks in trouble. If people can wait to buy a car, they’ll wait.’’