DPF deletion, MOT's and the law?

Akagi

Akagi

Akagi

Caporegime
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I read on a gov.uk page written in 2013 that MOT's now include a DPF check for vehicles which would have come with one as standard and that vehicles will fail if it has been removed.

First and foremost, is it true that it has been illegal for so long? Tuning companies have provided remap and DPF delete services for ages. Has this been stopped now?

Secondly, do the checks MOT testers carry out (if they do) actually include checking inside the DPF housing? If it is simply a visual check, could you just remove the internal filter itself?

I honestly didn't realise that the law had changed.

https://www.gov.uk/government/news/new-rules-for-mot-to-test-for-diesel-particulate-filter
 
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I think it came in at the beginning of 2014 if I am not mistaken and it is just a visual check AFAIK so if you gutted the DPF you would be OK, if you have replaced it with a pipe it would fail. That was my understanding but could be wrong!
 
at the moment it is only a visual check that they can carry out as long as they dont have to remove any covers to get to it. If it looks to have been tampered with then they can fail it

Alex
 
It's easy to check with a laser thermometer though. Measure the temp both sides of the DPF, if there isn't a difference across it then the innards have been removed.

If, at some point in the future an ODB scan forms part of the MOT (as I believe already happens in Germany) then the lack of any regen cycles will also be flagged.
 
So moving forward, DPF deletion is a no-no then basically.

Are there alternatives to DPF deletion which are legal, such as replacing the DPF with a smaller and less restrictive one?

I think I read somewhere that someone with an Alfa 2.4 JTDM replaced his dual DPF's with a single smaller "racing" DPF?
 
Acme said:
So moving forward, DPF deletion is a no-no then basically.

Are there alternatives to DPF deletion which are legal, such as replacing the DPF with a smaller and less restrictive one?

I think I read somewhere that someone with an Alfa 2.4 JTDM replaced his dual DPF's with a single smaller "racing" DPF?
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Are you thinking of Catalytic converters here rather than DPFs? It's not uncommon to get sport cats, but I've never heard of a sport/less restrictive DPF. Stranger things have happened though I guess.
 
iaind said:
Your car doesnt have a DPF?
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I think it's clear he's looking into cars again :p

Seems from a quick google that "Sports DPFs" are a thing, it seems they're bigger and therefore less likely/take longer to clogg up meaning they don't need to regen at all/as often. But also you can get your car coded to not regen at all... Not sure how beneficial all of that is.
 
I don't understand. The entire point of diesels is to save money on fuel. Therefore spending money on performance bits for them defeats the point somewhat surely?
 
Marvin said:
I don't understand. The entire point of diesels is to save money on fuel. Therefore spending money on performance bits for them defeats the point somewhat surely?
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It's to maximise efficiency vs performance
 
That sounds like a superb waste of time. Say you spend £500 on a "performance dpf" (lol) to maximise power in your diesel - you'd have to drive 14,000 miles to break even on the fuel. And that's before any other repairs or mods which may be diesel specific and come up along the way. I also suspect £500 is on the cheap side too. But the point is, for every £100 you spend modifying a diesel to perform more like the petrol equivalent, you have to cover 2,800 miles to pay for it in fuel savings.

If you want to go fast, buy a petrol. If you want to go fast in a diesel, buy a fast diesel. If you absolutely have to do 54mpg then buy a 1.6 diesel of some sort and leave it alone because you'll only break it anyway.

Brb, going to fit a racing glovebox
 
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[TW]Fox;28004804 said:
Racing DPF :D:D:D
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That's not what I would call it. I put it in quotation marks for a reason! :p

Someone on Autotrader is selling their 2.4JTDM which is mapped to 260HP and he said it had a "racing" DPF. :p

rodenal said:
Acme are you going to bolt a dpf somewhere in your polo engine bay, then remove it and see if the mot tester notices......?
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Ha :D Not exactly. I may have to look into a diseasal if I get one of the jobs I have been interviewed for recently, and I really don't want one with a DPF.

I thought it would be quite obvious that I know my 13 year old Petrol Polo doesn't have a modern DIESEL particulate filter. I'm not a total spanner. :rolleyes:

And I know the difference between a cat and a dpf. I know a lot more about cars than people give me credit for... The knowledge just gets tainted by some of the stupid things I say/do. :rolleyes:
 
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People remove their cats on petrol cars and either have a 'friendly' MOTer or just put them back on for the MOT and take them off again. Whether it is a criminal(?) offence to do that or not I am not sure - I think it is one of those grey areas. Presumably the DPF would be the same thing.

Please stop saying "delete"!
 
Everyone seems to say "delete" when talking about removing something from a car. Enthusiasts, garages, tuning specialists etc. DPF Delete, Cat delete, centre silencer delete, MAF delete, EGR delete, delete delete DELETE. :D
 
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