Meanwhile, Mercedes-Benz says it sold 13,812 vehicles in China in August, up 3 percent.

This year, Audi has had difficulty meeting customer demand for the Q5 crossover plus the stretched versions of the A4 and A6 sedans. Audi vehicles share a production line with Volkswagen models at the Changchun plant of FAW-Volkswagen Automobile Co., a joint venture between China FAW Group Corp. and Volkswagen AG.

In July, FAW-VW decided to allow Audi to use more of the Changchun plant's capacity. This capacity expansion has allowed VW to expand production of those three Audi models.

In August, Audi's sales of locally produced vehicles rose 21 percent to 22,851 units.

Sales of imported Audi models jumped 56 percent from a year earlier to 5,007 units. Audi imports the stretched A8, plus the Q7, R8, A5, W12 and TT. Later this year, the German luxury brand plans to introduce its A1 and A7 Sportback.

While Mercedes sales rose modestly in August, its sales for the first eight months jumped 36 percent to 120,234 units. But in China's luxury sales race, Mercedes remains in third place, trailing Audi and BMW.

To gain market share, Mercedes-Benz says it is preparing to add new models. Later this year, the automaker will begin Chinese production of the redesigned C-Class sedan. Mercedes also will launch sales of the SLK, C-Classcoupe and the CLS in China.