Fuel Additives and Retrofit Devices

A retrofit device or fuel additive is a product that, when installed or added to the fuel of a vehicle, will decrease exhaust emissions and/or increase fuel economy. Inspection and maintenance (IM) data, literature, tapes and California Air Resources Board Exemptions have historically not supported the claims that a device reduces exhaust emissions or saves fuel.

ADEQ does not maintain a program to evaluate or certify the effectiveness of retrofit devices or fuel additives to reduce exhaust emissions. All inquiries for evaluation or certification are referred to U.S.EPA or the State of California; both of which maintain programs that provide technical assistance in the development of test protocol and the evaluation of the product(s) effects on emissions/fuel economy. These programs use the complete federal test procedure, as described in the Code of Federal Regulations (CFR), Title 40, Part 86, which is the only valid test for device evaluation.

Modification to a vehicle without using certified parts and following an approved process may result in IM test failure. Installing a retrofit device on a vehicle without a reasonable basis for knowing that the device will not adversely affect a vehicle's emissions may result in civil penalties.

Related links:

California Air Resources Board, Aftermarket Parts Section

Code of Federal Regulations (CFR), Title 40, Part 86

National Vehicle and Fuel Emissions Laboratory

Fuel Additives