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Engine Family Search

Search by engine family number to look up the Smog Score for any vehicle dating back to the 2000 model year. For vehicles manufactured after January 1, 2009, you can also look up the Global Warming Score. The engine family number can be found under the vehicle's hood on the Vehicle Emissions Control Information Label. Start your search by entering your engine family number here:

Engine Family

What is an engine family number?

An engine family number is a number given to a specific engine used by a manufacturer. Auto manufacturers might use the same engine in many different vehicle models, or they may use several different engines within the same vehicle model. The engine family number identifies which engine is used, and it is important because a vehicle’s emissions are certified by engine family. So, two seemingly identical vehicles may have very different pollutant levels because their engines may be different.

Typically, vehicles sold in California and states that have adopted California’s emissions regulations will have cleaner engines (identified by their engine family number) than those sold in other states. A vehicle’s engine family number (sometimes called a “test group”) can be found under the hood of the vehicle on the Vehicle Emissions Control Information Label.

Here is an example of what the VECI label might look like. Each manufacturer’s label looks a little different, but they all have the same basic information, including the engine family or test group number.

How is an engine family number search useful?

Search for a used vehicle with the cleanest smog rating

If you are considering buying a used vehicle that you think might have a clean Smog Score, you can double check by looking up the engine family number. Just look under the hood of the vehicle and write down the engine family number, or test group number, and type it in on this search page. You will know right away what the smog rating is of that particular vehicle, and you can then find any other versions of that vehicle that might have a different engine – and a different Smog Rating.

Determine the environmental impact of the vehicle you are driving

If you are wondering what the Smog Score is of the vehicle you are currently driving, one way to be certain is to search by engine family number.

Think clean and buy cars with higher scores.

Find Clean Vehicles

Slide arrows to view vehicles by rating. Rating of seven or higher are the cleanest.

Greenhouse Gas

Smog Rating

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