Emissions-related MoT failures have double since introduction of tougher MoT rules

Published 20 November 2018

The number of cars failing the MoT due to excessive tailpipe emissions has double since the introduction of tougher rules for petrol and diesel engines, official figures show.

>>>Everything you need to know about the MoT rules and the 2018 updates

Data from the Driver & Vehicle Standards Agency (DVSA) show that nearly 750,000 cars have failed the tougher emissions test, since the MoT rules were updated six months ago on 20 May 2018, compared to 350,000 failing during the same period in 2017.

The 2018 MoT rules introduced lower default limits for tailpipe emissions and instant failures for Euro5 diesels that emit visible smoke. The DVSA also introduced a failure category for cars that have had their diesel particulate filter removed or tampered with.  

>>>See the MoT pass and failure rates for every car in the UK

The MoT rule change also introduced new defect categories, with test faults being listed as Minor, Major or Dangerous. Any car that gets a Dangerous fault fails and is deemed illegal to be driven on the road. A Major fault also results in a fail and be subject to a repair and retest. Minor defects are considered along the same lines as advisories, allowing the vehicle to pass with the faults being noted to the MoT history.

The DVSA says roughly 16 million vehicles have been tested by the new MoT rules, while the failure rate for petrol and diesel has remained broadly the same with 34.7 per cent of petrols failing compared to 33.2 per cent of diesels - the 2017 rates were petrol - 35.7 per cent and diesel - 33.8 per cent.


Sir Kevin Parr, Baronet    on 26 November 2018

Sorry but this is aimed only to convert us to using electric cars to suit Governments only. No engine can run well without gas and rubbish outlet or not run well. Can we humans be tested be tested too. Laugh but soon in this mad rush to get rid on millions of good cars will they be testing us for emissions too. Nothing can run if gas cannot be released engines are oil burning so to be best at running smooth. Horses f*** like hell at work.Stand behind a farm ploughing team and see and hear emissions. Space race tore out protective layer to shreads but it must be us you pay for it in the end. If all the cars ran in UK for 200 years it would not reach one cup full of emission next to the chimneys and factory smokes of 1950s They in power cant prove Im wrong as i know before I said this research facts will prove in court this is insane lies from State Control.Governments who cut down rain forest should be shot not blame cars for doing all the damage.

Birsay Bob    on 26 November 2018

I can cope with my vehicles being scrapped if they fail emission tests.After all Londoners lose on average 18 months of life due to pollution so fair enough
However I expect these tests to be applied to buses,ships,aircraft as well to ensure a level playing field.
You are just as dead breathing their pollution??
Bob Heddle

Peter Collard    on 26 November 2018

Using premium fuel and aftermarket fuel additives like taxi drivers do to keep older cars within emission criteria seems fair . My 2007 Land Rover has done 163,000 miles and passes its Mot , and I would say it’s quite an old polluter in my personal view , but it costs the planet a huge quantity of CO 2 to build me a replacement .

Edited by Peter Collard on 26/11/2018 at 13:35

R Coopey    on 26 November 2018

I rue the day when my 1999 Pug 106 diesel finally succumbs to the dreaded rust.
It's done 252,000 miles this far, always returning 60 + mpg.
In that time it's had one new clutch,and the usual tyres / brakes.
When I read of newer cars needing expensive repair work, often at a much lower mileage than my old Pug, I wince.
Needless to say, I do all I can to keep mine on the road.

Robert McAuley    on 26 November 2018

You've forgotten to add shipping as a huge polluter but what gets me is that the UK stick to the rules whilst other countries as USA, China, India, Germany etc burn vast quantities of coal , the latter using lignite which is the most polluting of all coals.

Old Toad    on 26 November 2018

Unfortunately we are an easy target but not the largest polluter. We appear to be the cash cow for the government and certain areas of the motor industry. Petrol prices increases (French public protests are an example0, 20 mph speed limit fines, yes in Birmingham last week, introduction of new congestion charges. Yes the government needs money, but little of what taken from the motorist is used to improve roads or other needs of the motorist.

   on 26 November 2018

The new rules introduced in May this year didn't change the petrol emissions test, only the diesel one. So the article is a bit misleading in that respect. So virtually all the increase in failures must be down to diesels. But do bare in mind that if a car fails but is then repaired and passes it will still show in the statistics as a fail, even though it may now be back quite properly on the road. And that, to me, is the value of the MOT test. Not to get cars scrapped but to get them safe and meeting the standards they should. What we should be worrying about are the few test stations which, I hear, aren't applying the new standards!

   on 26 November 2018

The only cars that fail are ones that are tested. There are lots of cars on the road that aren't tested, they don't have road tax or insurance. There are quite a lot of smelly cars. If your car is running properly, the exhaust fumes are odourless, petrol or diesel, but some exhaust are really smelly. We are breathing in these more toxic emissions.

John of Gloster    on 29 November 2018

To illustrate a point, lets say lil' ol UK becomes a near Zero emissions zone with all the clueless "We know best and must be seen to be doing the correct GREEN THING as we did when recommending Diesels and penalising nasty Petrols" updated action.That was two decades ago in the UK.

If the rest of the world still carry on our efforts would be a total waste anyway. Those we entrust our well being sucked up the expert EU opinion and made it so. Some of us at the time stressed the wrong stuff was being measured with diesels. Banging the bad-Diesel drums loudly. Nothing done for years by the clueless. What is truly amazing is that it took so long for the reality as diesel excrement to hit the fan for the clueless.

It's not just pollution which may, repeat may be responsible for Londoners ( that's me now an ex-Londoner folks ) dying prematurely. The stress levels living in the madhouse London has evolved into plays a far larger part in that. Anyway, lets blame Diesels and Petrols as the sole reason.... Green stuff vendors satisfied so all's well in the former green and pleasant.

I am on record years ago and more recently suggesting anyone watching their Diesel being tested would be amazed that any passed their emissions part of the test. Once the fug had cleared from the test centre. However, they did pass.

Those that allowed those erroneous Diesel guidelines to be introduced should be made to stand immediately behind their diesel vehicle prior to and during the emissions part of their diesel vehicle test... taking deep breaths all the time. Just maybe they will then get the message... BEWARE EXPERTS... many speak with forked tongue particularly those folks in Brussels. They've been measuring the wrong stuff! How convenient! Guess which manufacturers benefited as a result.

Now the harmful Diesel fug has dispersed...you should be able to see for miles...

All clear now ............?

   on 30 November 2018

I have a gas car which is far more emission efficient, but LPG seems to be loosing it's popularity with gas stations stopping selling Autogas - why?
My car has exceeded 300,000 without any real major repair and gas keeps the engine clean.
Vauxhall were smart in utilising an old 8 valve engine for their Duelfuel. The valves don't wear out. I have had a new injection front end installed at 170,000. Thats all!!

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