The practice of removing or disabling emissions control devices from vehicles, often referred to colloquially as “deleting,” has been a topic of regulatory scrutiny. These devices, such as catalytic converters and diesel particulate filters, are mandated by environmental regulations to minimize air pollution. Removing them can increase vehicle performance in some instances, but also substantially elevates harmful emissions.
The enforcement of regulations pertaining to vehicle emissions standards has fluctuated historically. Environmental Protection Agency (EPA) regulations have generally prohibited tampering with emissions control systems. However, interpretations and the degree of enforcement have varied across administrations and jurisdictions, leading to confusion regarding the legality of such modifications. The costs associated with maintaining these devices are also a motivating factor for some individuals considering their removal.