If your car is in a state where it would fail an MOT you're driving without a valid MOT and thus driving without insurance AFAIK
DPF deletion, MOT's and the law?
- Thread starter Akagi
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If your car is in a state where it would fail an MOT you're driving without a valid MOT and thus driving without insurance AFAIK
Caporegime
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Do any of the Diesel 24hr Le Mans race cars have a DPF?
If so then a 'racing' DPF does indeed exist!!!!!
If so then a 'racing' DPF does indeed exist!!!!!
Yes but your forgetting that the majority of people now have a distorted view that diesels are also faster than petrol with all that torque bro
when they forget that most diesel options have a Turbo and the petrol's don't.I even work with a few people who must do about 7k per year max and have just purchased diesels because the dealer probably brainwashed them into thinking its some kind of hot hatch with its turbo and torque.
What? No.
You're car is only MOT fit at the very moment it is passed, by your reasoning anyone who fails an MOT could be done for not having insurance.
Yes but your forgetting that the majority of people now have a distorted view that diesels are also faster than petrol with all that torque bro
Well they are.
If you are towing a bus up a cliff face.
Also no Hypernuts. No.
That would mean my insurance is invalid right now because of my err...thing.
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Thought that's what it was, if your car fails an MOT surely it's unroad worthy?
Man of Honour
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Nope.
Imagine if a CV joint started leaking (e.g. front constant joint velocity gaiter deteriorated). this is not something you can easily see without doing an inspection - this is often an advisory or even can be a fail in some instances I think. That can happen after your MOT - as long as your car passes the MOT at the time of the MOT that's all you need.
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Yes but your forgetting that the majority of people now have a distorted view that diesels are also faster than petrol with all that torque bro
Not really true any more, most petrol engines are now turbocharged as well.
The BMW range for example does not contain a single engine which does not have a turbocharger fitted whether petrol or diesel. It's the same for many other manufacturers now.
The diesels at Le Mans (and WEC in general) can be black flagged if they are emitting too much black smoke, so they are certainly running some form of particulate removal, plus very carefully set up injection to avoid over fuelling.
Soldato
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I thought it was illegal to remove a cat or dpf anyway.
Also if having a DPF is an issue for you then why bother getting a diesel in the first place.
Provided you do the correct sort of driving and allow it to regen then its a complete non-issue. Personally I've yet to have any DPF issues, a couple of times it has started to regen just as I pull into the driveway. I just let it do its thing and all is well.
If I turn the engine off in the middle of a regen then it will simply try again next time. I guess if you repeatedly/never allow it to regen fully then that is when people have problems with it.
Also if having a DPF is an issue for you then why bother getting a diesel in the first place.
Provided you do the correct sort of driving and allow it to regen then its a complete non-issue. Personally I've yet to have any DPF issues, a couple of times it has started to regen just as I pull into the driveway. I just let it do its thing and all is well.
If I turn the engine off in the middle of a regen then it will simply try again next time. I guess if you repeatedly/never allow it to regen fully then that is when people have problems with it.
Because I honestly believe that DPF's are absolutely stupid and pointless inventions and their existence irks me... They stop harmless soot from coming out of the back, then use diesel to burn/clean the soot out. Which... means it comes out the back anyway, just in a shorter space of time!!?!
The presence of a DPF is surely more harmful to the planet than not having one anyway.
Plus they are restrictive and reduce performance and economy.
The presence of a DPF is surely more harmful to the planet than not having one anyway.
Plus they are restrictive and reduce performance and economy.
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thanks for the explanation and the above link
Nothing to do with reducing Particulate emissions particularly in built up areas then?
Wikipedia Diesel Exhaust said:
Yep - move along, nothing to see here - completely harmless
So the same as Catalytic converters then? They are made of rare earth metals, typically reduce performance, but the vast majority of us have accepted that they are necessary to reduce harmful Carbon Monoxide emissions.
Arguably one of the reasons for DPF and further diesel emission reductions (e.g. AdBlue) is because people started buying diesels because they are in low VED bands, and were exempt from Low-Emission zones at the time.
Information on different types of DPF and re-gen systems.
I'm beginning to understand that now, watching this 30 minute DPF presentation.
It seems that some DPF regeneration systems use differential pressure sensors to detect the change in exhaust gas pressure before and after the DPF, to decide when the DPF is clogged enough to warrant a re-generation. This is fine, that makes complete sense. If the car is driven on long runs, it may never need to re-gen the DPF.
However some other systems re-gen the DPF based on fuel burned, mileage, or other factors, so they might initiate a DPF re-gen when it doesn't need doing at all.
When it comes to the actual re-gen process;
VW seem to have the right idea by putting the DPF pretty much immediately after the manifold, so that the exhaust gas is hot enough to burn the soot all the time, and they dont need a re-gen cycle.
Others systems inject diesel into the exhaust so that the heated gasses flow through the DPF and clear out the soot, and they do this on the exhaust stroke. Similarly some GM engines have an injector inside the exhaust system to puff diesel in just before the DPF. These sorts of system combined with the differential pressure sensor, would be in my eyes an almost perfect design. (second only to the simplicity of the VW design) Though the former which injects diesel on the exhaust stroke can apparently cause oil contamination (fuel getting into the oil). Is this sort of thing taken into account in the manufacturers oil change interval?
However some systems seem to just rev up the engine so that the whole exhaust heats up and the gas is hot enough to burn out the DPF? What rubbish! Is that true?
I don't want my car to sit there wasting diesel for 5 minutes, being all smelly and loud, because a manufacturer couldn't be bothered to implement an effective system.
Is there a resource somewhere which would tell me what manufacturers use what DPF re-gen systems?
I'm beginning to understand that now, watching this 30 minute DPF presentation.
It seems that some DPF regeneration systems use differential pressure sensors to detect the change in exhaust gas pressure before and after the DPF, to decide when the DPF is clogged enough to warrant a re-generation. This is fine, that makes complete sense. If the car is driven on long runs, it may never need to re-gen the DPF.
However some other systems re-gen the DPF based on fuel burned, mileage, or other factors, so they might initiate a DPF re-gen when it doesn't need doing at all.
When it comes to the actual re-gen process;
VW seem to have the right idea by putting the DPF pretty much immediately after the manifold, so that the exhaust gas is hot enough to burn the soot all the time, and they dont need a re-gen cycle.
Others systems inject diesel into the exhaust so that the heated gasses flow through the DPF and clear out the soot, and they do this on the exhaust stroke. Similarly some GM engines have an injector inside the exhaust system to puff diesel in just before the DPF. These sorts of system combined with the differential pressure sensor, would be in my eyes an almost perfect design. (second only to the simplicity of the VW design) Though the former which injects diesel on the exhaust stroke can apparently cause oil contamination (fuel getting into the oil). Is this sort of thing taken into account in the manufacturers oil change interval?
However some systems seem to just rev up the engine so that the whole exhaust heats up and the gas is hot enough to burn out the DPF? What rubbish! Is that true?
I don't want my car to sit there wasting diesel for 5 minutes, being all smelly and loud, because a manufacturer couldn't be bothered to implement an effective system.
Is there a resource somewhere which would tell me what manufacturers use what DPF re-gen systems?
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Soldato
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You have over simplified that just a little....
Revving the engine?
DPF regen requires relatively high speed cruising to provide adequate load and hence heat energy. I know of no system that does high speed idle for regen, the airflow running over the car is very usefuel when dealing with the external temps they get to.
For example its the high heat energy in the DPF thats leading to EGR systems that take exhaust after the DPF and then run through a larger low pressure EGR cooler before getting back into the intake manifold. Otherwise under regen its just too hot to use pre DPF.
Diesels are a nightmare. I will never buy one with my own money
Revving the engine?
DPF regen requires relatively high speed cruising to provide adequate load and hence heat energy. I know of no system that does high speed idle for regen, the airflow running over the car is very usefuel when dealing with the external temps they get to.
For example its the high heat energy in the DPF thats leading to EGR systems that take exhaust after the DPF and then run through a larger low pressure EGR cooler before getting back into the intake manifold. Otherwise under regen its just too hot to use pre DPF.
Diesels are a nightmare. I will never buy one with my own money
its not dpf's u should be stressing about Acme its the amount of harmful crap that comes out of diesel cars compared to petrol that is actually a far worse genuine threat to are health.
And what makes it worse is the rising amounts of them on our roads that are paying less tax than petrol versions but are far worse for serious emissions.
Just yesterday as i was crossing the road a van sped off at the lights that must have had its dpf removed or something as it left the biggest cloud of black smoke lingering in the air for about 5 seconds in my face which i would have then breathed in.
Anyone watch this dispatches prog "The great car con" from channel 4 a while back?
http://www.channel4.com/programmes/dispatches/on-demand/59670-003
And what makes it worse is the rising amounts of them on our roads that are paying less tax than petrol versions but are far worse for serious emissions.
Just yesterday as i was crossing the road a van sped off at the lights that must have had its dpf removed or something as it left the biggest cloud of black smoke lingering in the air for about 5 seconds in my face which i would have then breathed in.
Anyone watch this dispatches prog "The great car con" from channel 4 a while back?
http://www.channel4.com/programmes/dispatches/on-demand/59670-003