MOT test changes in 2018, what are they and how could they affect you?

Tougher emissions checks for diesel cars and new pass and fail categories to be introduced

Words By Claire Evans

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From 20 May 2018 the MOT test is becoming stricter in a number of areas. The changes are being brought in to adhere to a European Union directive called the EU Roadworthiness Package.

There will be tighter scrutiny of diesel cars’ particulate filters and faults on cars will be classed as Minor, Major or Dangerous.

Minor faults are comparable to the current β€˜advisory’ notices written on test certificates by MOT testers for items that aren’t bad enough for the car to fail its test, but will need to be fixed at some point.

Faults classed as Major will require the car to be fixed and retested. And those categorised as Dangerous will make it illegal for the car to be driven on public roads as well as automatic failure of the MOT.

How is the MOT test for diesel cars changing?

The most significant area for diesel car owners is stricter rules on the permissible level of emissions of cars fitted with a diesel particulate filter (DPF). If a car’s exhaust emits β€œvisible smoke of any colour”, it will be issued with a Major fault and will fail the test.

MOT testers are also required to check if the car’s DPF has been removed or tampered with. If it has, the tester must refuse to test the car unless the owner can provide a β€œlegitimate” reason for it having been removed, such as for cleaning.

What else is changing on the MOT test?

Three other areas on cars that have the potential to cause serious accidents are also going to be scrutinised more closely than before. Testers will check steering systems – a steering box with a heavy leak will result in a MOT failure, as will reversing lights that don’t work or have blown bulbs and brake discs that are β€œsignificantly or obviously worn”.

How will the changes affect you?

If you own a diesel car with a DPF that has been replaced or repaired you’ll need to show evidence of this to the MOT tester.

Blown light bulbs, worn out windscreen wipers and tyres with too little tread depth account for nearly 50% of failures, so it’s well worth checking these areas before taking your car for its MOT.

If you're buying a diesel-engined car check if it has a DPF – if it does, ask if it's had any problems and check the dash for an orange warning light that may look like an exhaust. If this is illuminated it means the DPF is becoming blocked - don't buy a car with this dash warning light on because it could indicate the need for a replacement DPF, which is likely to cost several hundred pounds.

It’s also worth regularly checking the car for leaks – this is easy to do by looking on the ground under the car for oil or other fluids that may have come from the car.

What are the most common MOT fail items?

Our top 10 reveals the most common reasons why cars fail their MOT test and simple tips to help you check these items before taking the test.

1. Brake lights

With the car’s ignition turned on, press the brake pedal and ask someone to check that the brake lights come on. You can also do this on your own by reversing the car up to a wall and looking over your shoulder.

2. Fuel and fuel cap

The filler cap needs to close securely and your car needs enough fuel in its tank for the tester to carry out emissions checks, so don’t go for an MOT test with the car running on empty.

3. Headlights and indicators

Check all the lights work properly, including full and dipped beam headlights, rear and side lights, hazard lights and all four indicators.

4. Horn

Beep it to ensure it works properly.

5. Numberplates

Ensure that both plates are clean and legible and check that the light above the rear numberplate is working.

6. Suspension

Press down heavily on each front wing of your car; if the car bounces up and down instead of returning to the right position, the shock absorbers may be worn.

7. Seat and seatbelts

Check that the driver’s seat slides back and forth smoothly, and look for fraying or damage on the seatbelts and give each one a good tug to ensure that it pings back as it should.

8. Wheels and tyres

Check all four wheels and the sidewalls of the tyres for damage; bulges, cracks and gouges out of the tyres are all fail items. Next, check the tyre tread depth is above the legal limit of 1.6mm; if your tyres have tread depth indicators, check that the tread hasn’t worn down to the level of the indicator. Alternatively, you can put a 20 pence coin into the area between the tread; if the raised part of the coin is above the tread, the tyre is too worn.

9. Windscreen

Check for chips and cracks; any crack larger than 40mm iwill result in a fail, and any crack or chip covering 10mm or more in the area the windscreen wipers clean is also a fail item.

10. Windscreen wipers

Check for splits or perishing on all wipers, and check that they clear the screens properly when they’re used. Also check and top up the screen wash if necessary.

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