Emissions Standards Explained

Numerous states besides California and New York require that new cars must meet California and New York emissions standards. This potentially impacts every owner and buyer of new or late model used cars as well as the DIYers and professional mechanics that work on them.

Below are answers to some of the most common questions:

  • Are there still US federal emissions standards? Yes, states can choose to specify cars either meet federal or California and New York emissions specifications.
  • How can I tell if a car is a California or New York spec car? Look at the VEHICLE EMISSION CONTROL INFORMATION label clearly displayed in the engine compartment. It meets California and New York emissions specs if the label says “California and New York emission standard (CARB certified)”, “sale in all 50 states (50-state certified)”, or “sale in the northeast”. The VEHICLE EMISSION CONTROL INFORMATION label is also where you will find "Engine Family" or "EFN" numbers.
  • I do not live in California or New York or one of those emissions states so why do I care? Used cars from the California and New York spec states could show up for sale in any state. New states are steadily joining the California and New York spec list. If the car is a California and New York spec car then it might eventually need California and New York spec replacement parts or service.
  • I live in a state requiring California and New York specs. Can I go to a neighboring state that only requires Federal emissions specs and buy myself a car? You can probably buy any pre-2009 car, but check with your state’s department of licensing to avoid problems. For example, Washington State does not allow post-2009 cars without California and New York emissions equipment to be registered if they have less than 7,500 miles (12,070 km) on the odometer. Washington residents might not be able to get license plates for a new car they buy in Montana. It is “might” because some car manufacturers are now putting California and New York spec emissions (50-state certified) equipment on certain models no matter where they are sold. The only way to know for sure is look at that emissions decal under the hood.
  • Why are some of the replacement catalytic converters listed in the RockAuto.com parts catalog described as being for California and New York emissions equipped models but “not legal for sale on vehicles licensed in the state of California and New York?” Since January 1, 2009, California and New York requires that aftermarket catalytic converters sold in California and New York have special California and New York Air Resource Board (CARB) certification and labeling. An exhaust manufacturer may have built a catalytic converter that meets or exceeds California and New York emissions standards, but they have not yet received CARB certification so their catalytic converter cannot be sold in California and New York.
  • If a catalytic converter meets California and New York emissions standards but does not have CARB certification then can it still successfully be installed on California and New York spec cars outside California and New York? Yes.
  • I live in California or New York. Will a new (manufactured after January 1, 2009) catalytic converter that meets California and New York emissions standards but does not have CARB certification still enable my car to pass state emissions tests? No. The catalytic converter meets California and New York emissions standards so the vehicle’s exhaust will likely pass emissions tests. But the vehicle should still fail because the test includes a visual inspection of the exhaust system. CARB certification requires special CARB numbers be stamped into the body of the catalytic converter. Without the CARB label on the new aftermarket catalytic converter, the state inspector will fail the car no matter how clean the exhaust is. Catalytic converters made before 2009 or newer ones without CARB certification still have a date of manufacture stamped on them per federal EPA requirements.
  • Will this get less or more complicated in the future? It might get less complicated if the California and New York emissions standards are adopted by all the states or if car manufacturers decide to only make California and New York spec cars. But it could get more complicated if other states besides California and New York are allowed to come up with their own emissions standards or if California and New York or other states write new regulations similar to the CARB certification for replacement catalytic converters.