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Companies in Md., Del., and Pa. settle alleged Clean Air Act violations involving after-market devices for diesel trucks

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PHILADELPHIA (May 28, 2020) – The U.S. Environmental Protection Agency today announced three settlements with vehicle repair shops involved in the illegal sale and installation of aftermarket devices that were designed to defeat the emissions control systems of heavy-duty diesel engines.

The companies – Innovative Diesel LLC in Elkton, Maryland; AirFish Automotive LLC in Laurel, Delaware; and Diesel Works LLC in Mt. Joy, Pennsylvania – allegedly violated the Clean Air Act’s prohibition on the manufacture, sale, or installation of so-called “defeat devices,” which are designed to “bypass, defeat, or render inoperative” a motor vehicle engine’s air pollution control equipment or systems.

Illegally-modified vehicles and engines contribute substantial excess pollution that harms public health and impedes efforts by EPA, tribes, states and local agencies to attain air quality standards.

Innovative Diesel agreed to pay a $150,000 penalty to resolve alleged Clean Air Act violations involving the sale of or offering for sale of defeat devices at its diesel truck repair facility. Innovative Diesel sold at least 4,876 devices designed to defeat emission controls on diesel trucks manufactured primarily by Ford Motor Co. The aftermarket products included hardware components and electronic tuning software, known as “tunes,” that hack into and reprogram a vehicle’s electronic control module to alter engine performance and enable the removal of filters, catalysts and other critical emissions controls that reduce air pollution.

AirFish Automotive agreed to pay a $32,333 penalty to resolve similar Clean Air Act violations associated with the sale of 30 aftermarket defeat devices at its facility in Laurel, Delaware. Additionally, AirFish Automotive offered for sale nine aftermarket defeat devices on its company web site.

Diesel Works agreed to pay a $22,171 penalty to resolve similar violations related to 18 sales and 15 instances of installation of performance tuning products, exhaust replacement pipes, and exhaust gas recirculation (EGR) delete kits. 

Today’s vehicles emit far less pollution than vehicles of the past. This is made possible by careful engine calibrations, and the use of filters and catalysts in the exhaust system. Aftermarket defeat devices undo this progress and pollute the air we breathe. The emissions impact depends on the original vehicle design, and the extent of the vehicle modifications. EPA testing has shown that a truck’s emissions increase drastically (tens or hundreds of times, depending on the pollutant) when its emissions controls are removed. Even when the filters and catalysts remain on the truck, EPA testing has shown that simply using a tuner to recalibrate the engine (for the purpose of improving fuel economy) can triple emissions of NOx.

As part of the settlements, the companies did not admit liability for the alleged violations but have certified that they are now are in compliance with applicable requirements.

These enforcement actions are part of EPA’s National Compliance Initiative for Stopping Aftermarket Defeat Devices. Since 2016, EPA has resolved more than 50 enforcement cases with companies that have allegedly manufactured, sold or installed hardware or software specifically designed to defeat required emissions controls on vehicles and engines used on public roads.

For more information on this initiative, visit: .

For additional examples, see EPA’s recent settlements with Performance Diesel, Inc., Punch It Performance, and Derive Systems. To view all closed vehicle and engine enforcement matters, please visit: .