EPA slaps Sinister Diesel with $1M emissions fine amid crackdown

The EPA this week announced $1 million in fines for a diesel performance parts manufacturer for tampering with emissions devices.

Sinister Mfg. Company, Inc.—doing business as Sinister Diesel—pleaded guilty to charges of conspiracy to violate the Clean Air Act and defraud the United States, and with violating the Clean Air Act by tampering with the monitoring device of an emissions control system of a diesel truck, according to an EPA press release, agreeing to pay a $500,000 fine.

The company must also pay an additional $500,000 fine under a simultaneously filed civil consent decree, which alleges violations of the Clean Air Act’s prohibitions on manufacturing or selling defeat devices used to disable emissions controls. The civil consent decree prevents Sinister Diesel from making these devices, and from transferring related intellectual property to other entities.

Pickup truck

“For close to ten years, Sinister Diesel sold parts designed to override or disable the emissions control systems on trucks,” said principal deputy assistant administrator Larry Starfield in a statement for the EPA’s Office of Enforcement and Compliance Assurance.

Citing court documents, the EPA said Sinister Diesel was engaged in selling parts and software used to disable emissions controls from its 2010 incorporation to April 2020. This illegal hardware and software has been marketed by multiple companies over the years, usually as a way to boost performance or allow diesel trucks to spew smoke—known as “rolling coal.”

According to the EPA, completely removing emissions controls can increase nitrogen oxide emissions 310 times, non-methane hydrocarbons increased 1,400 times, carbon monoxide increased 120 times and particulate matter increased 40 times.

Pickup truck

The EPA also noted that a 2020 report by its Air Enforcement Division found that more than 500,000 diesel pickup trucks in the U.S.—approximately 15% of U.S. diesel trucks manufactured with emissions control systems—had emissions controls illegally defeated. That report also found that buyers may be unaware that modifications to their trucks are illegal.

The EPA has been cracking down on violators for the past several years, though. Last year it fined one violator, Pennsylvania’s Keystone Automotive, $2.5 million. TV’s “Diesel Brothers” were levied an $800,000 fine in 2020.

Diesel trucks aren’t the only vehicles with defeat devices. Harley-Davidson was ordered to pay a $12 million fine in 2016 for selling “competition only” devices for motorcycles that it knew were used on-road. In an about-face from flouting emissions laws, it’s since started offering the electric LiveWire brand of motorcycles.