Test Group Search
Search by test group number to look up the Smog Rating for any vehicle dating back to the 2000 model year. For vehicles manufactured after January 1, 2009, you can also look up the Greenhouse Gas Rating. The test group number (sometimes called an “engine family number”) can be found under the vehicle's hood on the Vehicle Emissions Control Information Label. Start your search by entering your test group number here:
What is a test group number?
All vehicles sold in the United States have a unique drive-train identifier called the "Test Group" or "Engine Family Number". This number allows owners, parts suppliers, and service providers to determine specifications and installed emissions control equipment of motor vehicles. Because many vehicles may have several different configurations, this number will provide specific information about the emissions control system and exact standards that a vehicle was designed to meet.
The Vehicle Emission Control Information label is located in the engine compartment in a clearly visible position, most often directly on the underside of the hood. The following diagram can help you locate your vehicles 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 test group or engine family number.
How is a test group number search useful?
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 test group number identifies which engine is used, and it is important because a vehicle’s emissions are certified by test group. 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 test group number) than those sold in other states.
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 Rating, you can double check by looking up the test group number. Just look under the hood of the vehicle and write down the test group number, or engine family 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 Rating is of the vehicle you are currently driving, one way to be certain is to search by test group number.
Think clean and buy cars with higher ratings.