Welcome to the Connecticut Emissions Program

Tampering with Emissions Control Systems is Illegal

The Clean Air Act prohibits tampering with emission control systems originally installed and certified by vehicle manufacturers.

Tampering is defined as the removal, disconnection, or modification of any emissions control systems, which renders one or more components ineffective. Examples include, but are not limited to, the removal of the catalytic converter, or light for the MIL indicator, bypassing the Exhaust Gas Recirculation (EGR) valve, Air Injection, or Diesel Exhaust Fluid (DEF) systems, etc.

Please be advised that tampering or the installation of devices that bypass, defeat, or otherwise render the vehicle’s emissions control systems inoperative, including the use of simulators with the intent to circumvent or defraud the required OBD test for the State of Connecticut, is illegal and subject to prosecution and civil penalties.