Total sales reached 1,1888,865 in the month with 600,956 passenger cars and 587,909 light trucks sold.
With sales all but derailed a year earlier due to a major earthquake in March, sales rose highest year-over-year at Toyota Motor Sales, where sales climbed 41.5 percent.
At Honda Motor Co. sales rose 30.9 percent. At Volkswagen Group, sales rose 32.4 percent in September compared to the year-ago period.
Among U.S. automakers, Chrysler posted the largest gain from 12 months earlier. With 142,041 vehicles sold, Chrysler sales rose 11.5 percent compared with September 2011.
Sales at General Motors rose a relatively paltry 1.5 percent on 210,245 vehicles sold, while sales at Ford Motor Co. fell 0.2 percent, Autodata said.
Year-to-date sales are up 23.9 percent at Chrysler, 5.3 percent at Ford and 3.4 percent at GM.
Among foreign brands, year-to-date sales are up 31.6 percent at Toyota, 24 percent at Honda and 32.3 percent at Volkswagen.