New car sales of Japan's Toyota Motor Corp in China plunged in September, the manufacturer said Monday, highlighting that its business in the country has become sluggish against a backdrop of semiconductor shortages. Sales in China for Toyota, Japan's largest automaker, fell 35.9 percent from a year earlier to 115,000 units last month, after decreasing 11.9 percent in August. Japan's carmakers operating in China are likely to continue suffering from acute semiconductor shortages, triggered by an expansion of coronavirus infections in Southeast Asia, for the time being, some economists said. Honda Motor Co saw new car sales drop 28.1 percent…