The tuner company has agreed to also stop selling defeat devices and offer to buy back devices that don't comply to the Clean Air Act.

Defeat devices, which are often sold to enhance engine performance, work by disabling a vehicle's emission controls, causing air pollution. As a result of enforcement efforts, some of the largest manufacturers of defeat devices have agreed to pay penalties and stop the sale of defeat devices.

Cobb Tuning and the EPA have reached a settlement related to the brand's tuners and software.

Cobb sold over 81,000 devices that disable emissions controls or alter engine performance. The tuner also sold over 8,400 exhaust pipe upgrades that fall foul of the Clean Air Act. The company must cease technical support and deny warranty claims for existing defeat devices.

Prominent performance brand Cobb Tuning has agreed to settle with the United States Department of Justice and Environmental Protection Agency after being accused of violating the Clean Air Act. The company is the latest in a string of tuners to be targeted over production of “defeat devices,