Martin Winterkorn, then-chief executive of German carmaker Volkswagen, and chief financial officer Hans Dieter Poetsch appear at the company's annual news conference in Wolfsburg in March 2013. (David Gannon/AFP/Getty Images)

Volkswagen’s massive emissions-cheating scandal already has begun battering the company’s sales, according to data released Thursday, as a monster month for the auto industry bypassed the German carmaker.

The company said its U.S. sales grew modestly in September, inching up 0.6 percent compared to last year, while each of the nation’s five biggest car brands reported sales growth of more than 10 percent.

Before the emissions scandal, analysts had expected VW’s sales to grow closer to 10 percent, said Alec Gutierrez, senior analyst at Kelley Blue Book, and the company’s tepid September growth could worsen further as October and November sales show the full brunt of the allegations.

“There’s not a lot of good news here,” Gutierrez said.

VW’s sales in the United States were a weak spot even before news broke that the company had installed software in about 11 million diesel cars worldwide that helped it cheat on emissions tests.

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But the revelation has battered Volkswagen’s reputation after years of touting diesel cars as eco-friendly and powerful. The company stopped selling diesels in the United States, where they account for nearly a quarter of its sales, midway through September.

“We would like to thank dealers and customers for the support of the Volkswagen brand,” Mark McNabb, VW’s U.S. chief operating officer, said in a statement. “Volkswagen will continue to work diligently to regain trust and confidence in our brand.”

VW’s luxury brand, Audi, which also was implicated in the emissions-cheating scheme, was a glimmer of hope for the company. Audi sales grew 16 percent, and the company says it had its best September sales in the United States.

That was in line with the rest of the auto industry, which grew because of strong Labor Day sales. Fiat Chrysler sales grew 14 percent; Ford, 23 percent; General Motors, 12 percent,;Honda, 13 percent; and Toyota, 16 percent.

The industry is on track to sell cars at a near-record rate this year as analysts expect automakers to approach a pace of 18 million cars a year.

Volkswagen admitted to installing software designed to cheat emissions tests in about 11 million cars worldwide. While the cars passed emissions tests, they released nitrogen oxide up to 40 times the level allowed by federal law. Here's what you need to know about the scandal. (Jorge Ribas/The Washington Post)