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  • FIRST POST
    • Craig1981
    • By Craig1981 11th Oct 18, 4:02 PM
    • 348Posts
    • 162Thanks
    Craig1981
    New MOT Diesel Emissions
    • #1
    • 11th Oct 18, 4:02 PM
    New MOT Diesel Emissions 11th Oct 18 at 4:02 PM
    Hi all


    trying to find out some info online, but all stems to the "new" rules for MOT only, and trying to find some first hand experience regarding the new emissions rules under the new MOT


    I have a 2012 2L diesel, it has a DPF, and the items I have found online suggest cars like mine will struggle passing the new MOT.


    just wondering if anyone has had MOT done on a newer diesel car with DPF since the changes come into force?


    many thanks
Page 1
    • Indout96
    • By Indout96 11th Oct 18, 4:12 PM
    • 1,854 Posts
    • 2,634 Thanks
    Indout96
    • #2
    • 11th Oct 18, 4:12 PM
    • #2
    • 11th Oct 18, 4:12 PM
    Mine went for MOT in September - 2012 Volvo C30 1.6D passed no problem. nothing on the letter you get (no cert now - all on line) and garage never mentioned it so assuming everything was way within spec.
    Understeer is when the front of the car hits the wall.
    Oversteer is when the back of the car hits the wall
    BHP is how fast you hit the wall
    Torque is how far you take the wall after you hit it.
    • Tarambor
    • By Tarambor 11th Oct 18, 4:36 PM
    • 3,659 Posts
    • 2,716 Thanks
    Tarambor
    • #3
    • 11th Oct 18, 4:36 PM
    • #3
    • 11th Oct 18, 4:36 PM
    trying to find out some info online, but all stems to the "new" rules for MOT only, and trying to find some first hand experience regarding the new emissions rules under the new MOT

    I have a 2012 2L diesel, it has a DPF, and the items I have found online suggest cars like mine will struggle passing the new MOT.
    Originally posted by Craig1981
    Yes you'll find idiots who drive sheds making all kinds of claims. If you haven't had the DPF deleted and there's no warning lights then it'll pass the test. Basically during the smoke test a car with a DPF filter can't emit any smoke. If you've had the DPF filter removed or gutted then it cannot possibly pass this test as it'll chuck black smoke out when revved.
    • forgotmyname
    • By forgotmyname 11th Oct 18, 4:44 PM
    • 27,768 Posts
    • 11,264 Thanks
    forgotmyname
    • #4
    • 11th Oct 18, 4:44 PM
    • #4
    • 11th Oct 18, 4:44 PM
    Diesels are not tested for emissions. They have a smoke test.

    As long as the DPF if fitted is still fitted and working then the test is exactly the same as before.

    The only difference now is they need to look for the DPF and fail it if its missing or appears to be tampered with in any way.

    And any visible smoke from a vehicle with a DPF is likely to fail.

    Scaremongering about the changes. If the CAT and DPF are still fitted and working its the same as before.
    Punctuation, Spelling and Grammar will be used sparingly. Due to rising costs of inflation.

    My contribution to MSE. Other contributions will only be used if they cost me nothing.

    Due to me being a tight git.
    • AdrianC
    • By AdrianC 11th Oct 18, 4:45 PM
    • 18,718 Posts
    • 17,087 Thanks
    AdrianC
    • #5
    • 11th Oct 18, 4:45 PM
    • #5
    • 11th Oct 18, 4:45 PM
    trying to find out some info online, but all stems to the "new" rules for MOT only, and trying to find some first hand experience regarding the new emissions rules under the new MOT


    I have a 2012 2L diesel, it has a DPF, and the items I have found online suggest cars like mine will struggle passing the new MOT.
    Originally posted by Craig1981
    If it's not broken, and hasn't been mucked about with, there's no reason it won't pass.


    The main difference is that post-2008 diesels are tested to the figure the manufacturer gave on a plate under the bonnet, instead of a generic limit, and that the engine management light isn't lit. Hardly a high bar.


    just wondering if anyone has had MOT done on a newer diesel car with DPF since the changes come into force?
    The test changed in May, and it's now October. I'd take an educated guess that getting on for half the 3yo+ cars on the road have been tested in that time...
    • Nasqueron
    • By Nasqueron 11th Oct 18, 5:00 PM
    • 5,816 Posts
    • 3,523 Thanks
    Nasqueron
    • #6
    • 11th Oct 18, 5:00 PM
    • #6
    • 11th Oct 18, 5:00 PM
    Adrian Goldberg did a report on 5 Live Investigates about the DPF removal industry back in September pre-change and they found plenty of dodgy MOT places that would sign them off with a DPF missing in a car they fixed for the investigation (before the new rules), I wonder if that will still be the case post changes, few quid to a mate to look the other way and keep on pumping out gunk. The danger really is the people who buy diesels and drive like petrol who are going to have all sorts of issues

    https://www.bbc.co.uk/programmes/b09bxgjd
    • motorguy
    • By motorguy 11th Oct 18, 5:37 PM
    • 17,604 Posts
    • 10,672 Thanks
    motorguy
    • #7
    • 11th Oct 18, 5:37 PM
    • #7
    • 11th Oct 18, 5:37 PM
    If you've had the DPF filter removed or gutted then it cannot possibly pass this test as it'll chuck black smoke out when revved.
    Originally posted by Tarambor
    No. This is not true.

    A well maintained diesel car without a DPF can and will pass the MOT smoke test.

    A diesel car without a DPF but in need of maintenance - for example badly worn injectors, turbo, pump, etc - wont though.
    "We have normality. I repeat, we have normality. Anything you still can't cope with is therefore your own problem."
    • AdrianC
    • By AdrianC 11th Oct 18, 5:55 PM
    • 18,718 Posts
    • 17,087 Thanks
    AdrianC
    • #8
    • 11th Oct 18, 5:55 PM
    • #8
    • 11th Oct 18, 5:55 PM
    A well maintained diesel car without a DPF can and will pass the MOT smoke test.
    Originally posted by motorguy
    If it's a pre-July 08 car, then easily. But after that... Much harder. It almost certainly won't hit the manufacturer's opacity limit, and would struggle to hit the levels of opacity for a generic post-08 test, though, and especially the post-Jan 14 level.


    And it should definitely fail on a missing DPF, unless it's been gutted in such a way as to be invisible when fitted.
    • Svein Forkbeard
    • By Svein Forkbeard 11th Oct 18, 6:37 PM
    • 547 Posts
    • 1,245 Thanks
    Svein Forkbeard
    • #9
    • 11th Oct 18, 6:37 PM
    • #9
    • 11th Oct 18, 6:37 PM
    https://www.gov.uk/government/publications/mot-changes-from-may-2018-guidance-for-mot-testers/diesel-vehicle-emission-limits#new-default-limit-for-newer-vehicles

    Be warned that the number on your plate may be lower on the plate than the default limit. There are ways round this which you may wish to discuss with your mechanic but probably not strictly legal.
    Hi, weve had to remove your signature. If youre not sure why please read the forum rules or email the forum team if youre still unsure - MSE ForumTeam
    • Nasqueron
    • By Nasqueron 11th Oct 18, 10:50 PM
    • 5,816 Posts
    • 3,523 Thanks
    Nasqueron
    No. This is not true.

    A well maintained diesel car without a DPF can and will pass the MOT smoke test.

    A diesel car without a DPF but in need of maintenance - for example badly worn injectors, turbo, pump, etc - wont though.
    Originally posted by motorguy

    It's a fail if they spot the DPF is gone though as it's illegal to drive a diesel that should have a DPF without one. Depends how well hidden away it is in the car
    • Craig1981
    • By Craig1981 12th Oct 18, 5:52 AM
    • 348 Posts
    • 162 Thanks
    Craig1981
    thanks all for your replies, it is re-assuring
    • Apodemus
    • By Apodemus 12th Oct 18, 7:46 AM
    • 1,083 Posts
    • 890 Thanks
    Apodemus
    My 59 plate, no DPF, 2.2 litre diesel passed its MOT yesterday, with no advisories. Exhaust is clean right up through the usual rev range, despite having over 100k miles on the clock. Not sure what revs they take it up to on the test, but I’d agree that for a well-maintained diesel, the current MOT rules should not be a problem.
    Last edited by Apodemus; 12-10-2018 at 7:50 AM.
    • sevenhills
    • By sevenhills 12th Oct 18, 10:29 AM
    • 1,631 Posts
    • 598 Thanks
    sevenhills
    My 59 plate, no DPF, 2.2 litre diesel passed its MOT yesterday, with no advisories. Exhaust is clean right up through the usual rev range, despite having over 100k miles on the clock. Not sure what revs they take it up to on the test, but I’d agree that for a well-maintained diesel, the current MOT rules should not be a problem.
    Originally posted by Apodemus

    Euro 5 (2009/9) for light passenger and commercial vehicles; if it has no DPF does it have adblue?
    Or are you saying it have been removed? I would have expected a EURO 5 to be quite a low emmissions vehicle, maybe its a EURO 4.
    Last edited by sevenhills; 12-10-2018 at 6:07 PM.

    • LandyAndy
    • By LandyAndy 12th Oct 18, 10:33 AM
    • 24,445 Posts
    • 51,609 Thanks
    LandyAndy
    My car, 2009, 2.2l with DPF, 154,000 miles, passed with no issue just after the new regulations were introduced.
    • AdrianC
    • By AdrianC 12th Oct 18, 11:00 AM
    • 18,718 Posts
    • 17,087 Thanks
    AdrianC
    Euro 5 (2009/9) for light passenger and commercial vehicles; if it has no DPFdoes it have adblue?
    Or are you saying it have been removed? I would have expected a EURO 5 to be quite a low emmissions vehicle, maybe its a EURO 4.
    Originally posted by sevenhills
    Euro5 (like all the other limits) doesn't actually mandate specific equipment. It simply sets a level that may or may not be possible to achieve without.

    The main changes from Euro4 to Euro5 for diesels were a reduction in NOx from 0.25g/km to 0.18g/km... and a reduction in particulates from 0.025g/km to 0.005g/km. HUGE reduction there, which is why most manufacturers decided DPFs were needed - but not all.
    • Apodemus
    • By Apodemus 12th Oct 18, 2:16 PM
    • 1,083 Posts
    • 890 Thanks
    Apodemus
    Euro 5 (2009/9) for light passenger and commercial vehicles; if it has no DPFdoes it have adblue?
    Or are you saying it have been removed? I would have expected a EURO 5 to be quite a low emmissions vehicle, maybe its a EURO 4.
    Originally posted by sevenhills
    Its a Euro 4.
    • Nodding Donkey
    • By Nodding Donkey 12th Oct 18, 3:11 PM
    • 2,620 Posts
    • 2,212 Thanks
    Nodding Donkey
    and keep on pumping out gunk.
    Originally posted by Nasqueron

    You realise that diesels with a dpf still pump out the gunk don't you.


    Just they do it all in one go when 'regenerating'.


    Biggest con ever.
    • AdrianC
    • By AdrianC 12th Oct 18, 3:52 PM
    • 18,718 Posts
    • 17,087 Thanks
    AdrianC
    You realise that diesels with a dpf still pump out the gunk don't you.

    Just they do it all in one go when 'regenerating'.

    Biggest con ever.
    Originally posted by Nodding Donkey
    No, not really. The particulates are burnt at a higher temperature, and disposed of in a less harmful ash form, rather than emitted as particulates.

    If they were just "pumped out" in "one go", you'd know instantly when a DPF car was regenerating, because it'd be...



    (Some American pick'em'up drivers think this is laudable, and deliberately turn the fuelling up to do it. They call it "rollin' coal"...)
    • sevenhills
    • By sevenhills 12th Oct 18, 6:11 PM
    • 1,631 Posts
    • 598 Thanks
    sevenhills
    No, not really. The particulates are burnt at a higher temperature, and disposed of in a less harmful ash form, rather than emitted as particulates.
    Originally posted by AdrianC

    And there is also the Adblue, in which the particulates are mixed with water vapour and fall to the ground instead of being breathed in.

    • AdrianC
    • By AdrianC 12th Oct 18, 6:28 PM
    • 18,718 Posts
    • 17,087 Thanks
    AdrianC
    And there is also the Adblue, in which the particulates are mixed with water vapour and fall to the ground instead of being breathed in.
    Originally posted by sevenhills
    Umm, no.

    AdBlue - urea - is used in a catalytic reaction to convert NOx emissions into nitrogen, water vapour and CO2. It's nothing to do with particulates.
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