Why Do MOT Tests Include the Emissions Test?

MOT tests include a strict exhaust emissions test to reduce the level of harmful pollutants like carbon monoxide and hydrocarbons that are released into the atmosphere.

As the UK government moves closer to achieving the goal of reaching Net Zero Emissions by 2050, reducing the greenhouse gases produced by transport has become even more important.

If your vehicle does not pass the emissions test, it will fail its MOT. As excessive emissions are quite severe, this will be deemed a major fault on the MOT test. To pass the MOT test and acquire an MOT certificate, you must have any issues causing your vehicle to fail the test fixed.

What Happens During the Emissions Test?

During the exhaust emissions test, a certified MOT tester will use specialist equipment to measure the gases produced by your car’s exhaust.

A probe – also known as an exhaust gas analyser – will be placed into the tailpipe of the vehicle. Your car will be turned on so that the levels of oxygen, carbon monoxide, carbon dioxide and hydrocarbons can be measured.

To pass the MOT test, there must be no visible smoke coming from the exhaust.

For diesel vehicles, the diesel emissions restrictions must not be exceeded, and your car’s diesel particulate filter (DPF) must not have been removed or tampered with.

Which Vehicles Have Their Exhaust Emissions Tested?

Most vehicles will have their exhaust emissions tested as part of the MOT test.

Whilst most vehicles are tested using a meter, petrol vehicles used before August 1975 and diesel vehicles used before January 1980 are tested by sight instead.

There are certain vehicles, however, which don’t sit an emissions test as part of the MOT inspection:

  • Electric Vehicles
  • Hybrid Vehicles
  • Quadricycles
  • Hydrogen Fuel Cell Vehicles
  • Vehicles with 2-Stroke Engines
  • Vehicles with Less Than 4 Wheels

In addition to the MOT test, some councils are now testing vehicles for their emissions at the roadside. You could be issued with a fixed penalty if your vehicle fails this test, so you should always be aware of your car’s emission levels.

Williams Garage Are Here to Help You Prepare Your Vehicle for the MOT Emissions Test

If you are at all concerned about your vehicle’s exhaust emissions, speak to a member of the capable Williams Garage team. We will be happy to discuss next steps with you, as we want your vehicle to have the best chance of passing the MOT test.

Our incredible team of expert technicians can help to reduce the level of exhaust emissions your car produces through regular car servicing and timely exhaust repairs. This, in turn, will increase your chances of passing the MOT emissions test, giving you the peace of mind that you deserve.

If your vehicle is due one, be sure to book an MOT in Winchester with Williams Garage. As exhaust emissions are one of the biggest reasons for MOT failure, you must ensure that your vehicle’s emissions control systems are working well by investing in regular maintenance ahead of the test.