Using the sniffer tool for an emission test.

Emission test required every two years

In Vehicle Maintenance by HomeTowne Auto Repair & Tire

Every two years, Northern Virginia drivers must have an emission test conducted on their vehicle.

This requirement applies to those who keep their cars in certain localities, such as Prince William County and the cities of Manassas and Manassas Park.

The emission test seeks to protect the environment by making sure the car releases the right amount of fumes into the air.

It is run by the Department of Environmental Quality (DEQ).

HomeTowne Auto Repair & Tire is an emissions shop. It became a Virginia Certified Emissions Repair Facility in 2017.

What happens during an emission test?

We confirm details about the car, including its weight and Vehicle Identification Number (VIN).

When testing a vehicle that’s older than 1996, inspectors use a sniffer tool that’s put inside the tailpipe. They also check for various components, including the catalytic converter, O2 sensors and the Evaporative Emission Control System (EVAP).

We use an OBD II connection device on newer cars. The DEQ computer plugs into the OBD II port on the car and checks for problem codes and system monitors.

Those monitors can include the EVAP system, catalyst (catalytic converter), 02 sensors, the EGR system, Oxygen Sensor Heater and secondary air system.

What can cause you to be rejected for testing?

There are a few ways you can be rejected for getting an emission test: if there are bald tires, an audible exhaust leak, or fluid that’s dripping on the dyno machine.

Why does that matter?

We have to make sure the vehicle is safe to run on the dyno, in case the DEQ requires it.

HomeTowne Auto Repair & Tire is an authorized Michelin and BFGoodrich tire dealer located in Woodbridge, Virginia. Automotive repair services are performed on all makes and models, including oil changes, brakes, alignments, inspections, and computer engine diagnostics.