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Importing Vehicles and Engines

Certification Guidance for Importing Vehicles and Engines

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If you are a vehicle, engine or equipment manufacturer seeking to obtain an EPA Certificate of Conformity, you will need to review information about EPA’s vehicle and engine compliance information system on the Verify website.  Verify collects emissions and fuel economy compliance information for all types of vehicles and engines.

Independent Commercial Importers (ICI)

An ICI is an entity that has obtained EPA credentials to import vehicles into the United States. ICIs must hold a current, valid EPA Certificate of Conformity for at least one vehicle model, are not the Original Equipment Manufacturer (OEM), and do not have a contractual agreement with the OEM to act as its authorized representative for the distribution of vehicles or engines into the United States market. ICIs act independently of the OEM, but must follow the same emission requirements imposed on OEMs by the Clean Air Act. More information on ICIs.

Alternative Fuel Conversions

Alternative fuel conversions involve modifications that enable vehicles or engines to run on different fuels than the ones for which they were designed and certified. It is generally a prohibited act to modify a certified vehicle or engine in a way that could affect emissions.  However, a modification for the purpose of enabling a vehicle or engine to operate on a clean alternative fuel may not constitute tampering if the modifier:

  • follows the manufacturer’s installation instructions AND
  • properly installs an acceptable conversion system. To be acceptable, the system must comply with EPA conversion regulations 

EPA regulations on clean alternative fuel conversions provide options for fuel converters to avoid a possible tampering violation when the vehicle or engine is changed from its original certified configuration to enable operation on the new fuel(s). A complete description of the Alternative Fuel Conversion program and links to the regulations.

NOTE: A testing exemption may be available to cover vehicles and engines that are modified to demonstrate compliance with EPA conversion regulations, or for other testing purposes. Such modification does not constitute tampering if the converter first obtains an EPA testing exemption. For information on how to obtain an EPA testing exemption, please:

  • send us an email at or
  • call us at the Imports Hotline at 734-214-4100.

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