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Q: How Do I Prepare for My Car's Emissions Test?

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How do I prepare for my car's emissions test?

The purpose of emissions test is to assist in keeping the air breathable and clean by requiring that vehicle emissions systems are working properly. When the emissions system is working properly, the amount of harmful pollutants that are emitted into the atmosphere is significantly reduced.

The type of test that will be required for your vehicle will vary depending on the vehicle model, year, and the area that you live in. Find out if emissions testing is required in your area. These are some of the types of emission tests that are used to check your vehicle’s emissions:

  • Gap Cap Pressure Test
  • On-Board Diagnostics (OBD-II) Test
  • Visual Inspection Test
  • Tailpipe Testing

Learn more about how your car is tested for emissions.

The way in which you should prepare for an emissions test varies based on the type of test you will be receiving and the particular state that you live in. The following list includes things to do to prepare for an emissions test and may or may not be entirely inclusive depending on your circumstances.

  • Make sure your gas cap is sealed tightly to make sure that it has been properly secured to the fuel inlet

  • Make sure you have a clean air filter in your vehicle. This helps to keep the emission system operating properly

  • Make sure that your brakes and brake pads are good

  • Make sure the front wheel drive has proper alignment

  • Make sure your vehicle does not having any fluid leaks

  • Some types of tests will require that the shift indicator works properly

  • Some types of tests will require that the driver’s side door is operational

  • Make sure that your Check Engine Light is not on. If your Check Engine Light is on, your car or truck will not pass emissions testing. It will be necessary to make repairs in order to clear the Check Engine Light from your dashboard prior to arriving for emissions testing.

  • Once necessary repairs have been completed, you will need to drive your vehicle for over 20 miles so that it is able to go through the proper drive cycles. Doing so will allow the diagnostic trouble code to be cleared from the powertrain control module (PCM) history and memory.

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