Car Sales Stall: Auto makers reported scant sales gains in early September, as the weak economy and the Labor Day holiday kept buyers away from dealer showrooms. Sales of U.S.-built cars and trucks in the Sept. 1-10 period were up 2.1% from a year ago to reach 236,473 vehicles. The seasonally adjusted selling rate for domestic cars and trucks advanced to 10.9 million units in the period, from 10.3 million in the same period a year ago and 11.6 million in the previous 10-day sales period. Among the Big Three, only General Motors Corp. saw sales decline, by 15% to 49,251, from 57,968 a year ago. Ford Motor Co. reported an 11.1% increase in car sales and a 5.4% gain in truck sales. Chrysler Corp. sold an estimated 38,850 cars and trucks in the early period, up 19.5%.