The What, Why & How

What Is It? Smog is a type of air pollution, originally used to describe the smoke and fog created by the burning of large amounts of coal within a city.  Modern smog refers to a type of air pollution caused by traffic emissions – such as from trucks, buses, and automobiles.  The smog in Los Angeles is an example of such air pollution.

Why Do Smog Tests?  The smog check makes sure vehicles meet the government’s requirements for environmental air quality and ensures cars with excessive emissions are repaired to reduce air pollution.  Smog tests are required in many states and counties – be sure to check your specific area’s requirements.

How It Works:  A smog test is performed by putting the vehicle on a platform where the front or back wheels drop down on a spinning tube.  This is so that your car can be accelerated without moving, while a sensor placed inside the exhaust pipe measures the exhaust emitted.  The sensor communicates this information to a computer, thereby displaying whether the vehicle passes the government’s standards.

Tips to Pass Your Smog Test:

• Make sure your exhaust system has no holes or leaks.  You can fail the smog test if your car emissions are too low as well.
• Replace any old hoses, air filters, and wires and check your oil.
• A warm engine is more likely to pass the smog test than a cold one.  Take a 20 minute drive prior to your smog test.

Getting your vehicle smog tested can be a hassle and an added expense, but the benefits far outweigh the cost to keep our air and our planet clean.