DPF delete = MOT failure!
- Thread starter ElliotB
- Start date
ElliotB
Registered User
Dear Mods, please allow the discussion on the subject - https://www.gov.uk/government/news/new-rules-for-mot-to-test-for-diesel-particulate-filter.
I think it benefits all knowing the risks. I'll be the first to admit that I was a little bit harsh for which I sincerely apologise
I think it benefits all knowing the risks. I'll be the first to admit that I was a little bit harsh for which I sincerely apologise
Hi,
My understanding of the DPF removal and the new MOT rules, is if it had one from the factory and it has been removed then it will fail. BUT its how the MOT tester will know what was fitted from the factory, as an example my A4 was available with or without a DPF, this info can be gained from the PR codes generated by the chassis number, but I don't think for one minute that the tester will have access to this information for all vehicles unless the logbook format is changed to reflect one being fitted. Then the question would be asked will it only include new cars from a certain date.
If I was looking for a DPF delete I would be looking at just gutting the DPF canister with the suitable software deletion, then for all intents and purposes it would appear that the filter is still fitted.
I think the rules they are bringing out recently are an attempt to combat what DVLA perceive as fraud as vehicles now have to be certified as regards to their emissions to qualify for lower road tax, by messing with parts of the system that affect the certified emission levels you are effectively altering and increasing the emission levels, therefore paying cheaper road tax than the changed emission levels would dictate.
ultimately its your decision but if the DPF system is working, then leave it alone until you have to make the decision about removing it.
My understanding of the DPF removal and the new MOT rules, is if it had one from the factory and it has been removed then it will fail. BUT its how the MOT tester will know what was fitted from the factory, as an example my A4 was available with or without a DPF, this info can be gained from the PR codes generated by the chassis number, but I don't think for one minute that the tester will have access to this information for all vehicles unless the logbook format is changed to reflect one being fitted. Then the question would be asked will it only include new cars from a certain date.
If I was looking for a DPF delete I would be looking at just gutting the DPF canister with the suitable software deletion, then for all intents and purposes it would appear that the filter is still fitted.
I think the rules they are bringing out recently are an attempt to combat what DVLA perceive as fraud as vehicles now have to be certified as regards to their emissions to qualify for lower road tax, by messing with parts of the system that affect the certified emission levels you are effectively altering and increasing the emission levels, therefore paying cheaper road tax than the changed emission levels would dictate.
ultimately its your decision but if the DPF system is working, then leave it alone until you have to make the decision about removing it.
ElliotB
Registered User
Andy in theory you can still remove the DPF without any signs. However it's still an offence. The government could go after garages (unlikely) but what most likely is that customers who have failed MOT with DPF removed would be very p*** off and that could result in few garages splashing on replacing DPFs because legally they are responsible.
Viking
****** Viking...
Technically, it isn't an absolute offence. The offence is to use a vehicle which has been modified in such a way that it no longer complies with the air pollutant emissions standards it was designed to meet, not to remove the DPF.
To be convicted of the offence it would need to be proved that the removal of the DPF caused the vehicle to be non compliant. That would take some doing. The car would need to be retested to the emissions standards (EURO 5) and would need to fail, then it would need to be proved that the removal of the DPF caused this failure. The method of doing this would be way beyond roadside plod checking for a DPF having been removed, and more in the lines of laboratory standard testing procedures.
So to simplify the procedure, the Government have simply said that if your car has had the DPF removed then it is an MOT fail. No testing to emissions standards needed. And again it's merely a visual check to see if it's still there, not a test of its functionality.
ElliotB
Registered User
"But it is an offence to drive a vehicle that has been modified this way, as it will no longer meet the emissions standards the car achieved when it was approved for sale in the UK." - I guess this is open to interpretation. But given what it says in the article it automatically becomes an offence. At least I see it that way
My car has a DPF but was built to EU4 Plus emission standards. This is actually marked on the vechicle build plate under the bonnet where the chassis number is and the axle weights.It's a 2008 car so didn't need to be built to EU5.
I cannot find out what a EU4 Plus emission standard is I suspect it's a VAG thing where they were in between EU4 and EU5 so basically it's an EU4 car with a DPF. So if it has to meet PM (Particulate Matter) levels for EU4 it doesn't need a DPF as it will do that easily as most EU4 cars don't have a DPF. Only cars that are EU5 on need a DPF to meet the emissions standards.
Karl.
I cannot find out what a EU4 Plus emission standard is I suspect it's a VAG thing where they were in between EU4 and EU5 so basically it's an EU4 car with a DPF. So if it has to meet PM (Particulate Matter) levels for EU4 it doesn't need a DPF as it will do that easily as most EU4 cars don't have a DPF. Only cars that are EU5 on need a DPF to meet the emissions standards.
Karl.
ElliotB
Registered User
It clearly states "The vehicle will automatically fail the MOT test if the filter had been fitted as standard but is found to be no longer present."
I think a fairer approach would be to ask to pay more Road tax, taking into account it looks like it applies retrospectively.
Saying that a portion of blame should also apply to car manufacturers when in the early days DPFs were quite unreliable.
I think a fairer approach would be to ask to pay more Road tax, taking into account it looks like it applies retrospectively.
Saying that a portion of blame should also apply to car manufacturers when in the early days DPFs were quite unreliable.
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ElliotB
Registered User
"Technically, it isn't an absolute offence. The offemissions s to use a vehicle which has been modified in such a way that it no longer complies with the air pollutant emissions standards it was designed to meet, not to remove the DPF" - technically they could argue that you were defrauding them by not paying the correct amount of road tax, which, correct me if I'm wrong, is at least partially based on the amount of air pollution
Viking
****** Viking...
They could do many things, most of which would be time and cash consuming. Instead they simply added a visual DPF check to the MOT test to prevent people from removing a DPF and then passing an MOT. Easiest and cheapest way of catching the majority of DPF deletes. In the same way that catalytic converters are managed. It's not an offence to remove a cat, nor is it an offence to drive a car without one fitted, but it's a contravention of Road Traffic regulations if the car doesn't pass the emissions it was designed to do. Note here that we're referring to "Regulations" rather than "Law". There is no Law that says you cannot remove a DPF, but removal of a DPF contravenes the Regulations. Despite many [knowledgeable] people saying "It's against the law!" etc.
If a test case went to Court for this issue, the charge would be Contravention of Road Traffic Regulations Act 1984, not Removal of a DPF.
ElliotB
Registered User
"This practice has always been illegal, contravening the Road Vehicles (Construction and Use) Regulation 61 A as it no longer meets emission standards applied to it when new, but companies continue to advertise the practice" - source MOT test fail for DPF removal | Auto Express, paragraph 5
I think they rushed with the term illegal though
Now I think I understand where you're coming from....
I think they rushed with the term illegal though
Now I think I understand where you're coming from....
I purchased a cheap B5 A4 few years back as I was going to break it, but I ended up running the car for a couple of years. When it went for it's MOT and it scrapped through on the emissions test, and was told it most likely needs a new cat. When I remove the old cat I was surprised to see that the stuffing had been knocked out, but other than that you could not tell. If people have just been hammering out the DPF and putting that back in the car, the only way to notice someone has modified the car would be a visual check of the tail pipes as on a car with DPF they should be fairly clean.
A visual check is never going to be good enough, DPF cars should be emissions tested to avoid this issue.
A visual check is never going to be good enough, DPF cars should be emissions tested to avoid this issue.
Viking
****** Viking...
The smoke test for a post 2008 car is much tighter then a pre 2008 car which would generally catch all the DPF equipped cars and keep them smoking less than the requirement. I'd expect in the future that the smoke test will be tightened even further as the efficiency and reliability of DPFs is improved. At present though, other than lab analysis I doubt there's any real world means of testing for particulate matter, so a smoke test is realistic. After all, the DPF's main job is to remove carbon & soot (smoke) from the exhaust gas.
Technology has to keep ahead of the regulations, and at present it is doing so. All this is taken care of by manufacturers and type approval before we ever get our hands on the cars, and they're working into the future looking at the next round of emissions changes due in later this year (Euro 6) and to come into force early next year. As technology moves forward, the regulations catch up, and vice versa. But it's a slow process.
hollows wife
Registered User
the equipment used in a standard mot station for a diesel smoke test is old technology and be quite easily be fooled with a 10 p biro pen .
and is the same test wether it is pre or post 2008 .
and is the same test wether it is pre or post 2008 .
