Toyota's Camry had been losing U.S. market share in a big way, but that suddenly changed in August. Photo credit: Toyota

Toyota's (TM -0.91%) Camry has been the best-selling car in America for a while now, but 2013 hasn't been its year. Through the first half of the year, Camry sales were actually down almost 3%. Fresh rivals from Ford (F 0.17%), Honda (HMC -0.75%), and Nissan (NSANY 0.54%) looked to be eating Toyota's lunch.

But suddenly in August, Camry sales were up almost 22%. What changed? The answer turns out to be pretty simple: Toyota resorted to one of the oldest tricks in the auto business. In this video, Motley Fool contributor John Rosevear looks at Toyota's new determination to "defend" the Camry -- and at what that's likely to mean for Ford and Toyota's other rivals.