Amid the Volkswagen emission scandal, the Environmental Protection Agency is investigating other auto manufacturers including General Motors (GM), Chrysler (FCAU), BMW, Land Rover and Mercedes-Benz - to see if similar efforts were employed to sidestep emission tests. The models the EPA is looking at are BMW's X3, Chrysler's Grand Cherokee, GM's Chevy Colorado, the Range Rover TDV6 and the Mercedes E250 BlueTec. Volkswagen made headlines in recent weeks, saying it used devices to fool emission tests for various diesel cars. The automaker's CEO and its U.S. CEO both resigned following news of the scandal. But Volkswagen's sales, at least right now, remain healthy. The troubled automaker posted a 0.6 percent year-over-year increase during the month of September. TheStreet’s Scott Gamm reports from New York.