Anyone scrap their TD5 cat pipe when they fitted decat?

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v8landyman

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I hope not, since you will now need one fitted to pass the MOT. This has been confirmed by my local friendly tester.

Very pleased that I kept mine, but what we really need is someone to make a decat front pipe with a dummy cat welded on.
 
anything about 300tdi's ?

If it had a cat fitted when it left the factory, then it will need one to pass the MOT, but you may get away with it as the tester will probably not have information that one was fitted to older vehicles.
 
If it had a cat fitted when it left the factory, then it will need one to pass the MOT, but you may get away with it as the tester will probably not have information that one was fitted to older vehicles.

Surely they have a book that would give them the info as to what vehicle, model and make, to follow the rules
 
So they are doing it retrospectively? Thought they couldn't do that? Mine still has its cat at the moment, but its not in great shape...

Does anyone know whether it applies to DPFs too? I think mine is knackered in my Mazda 6, but its £1200 for a new one, or £400 to get it removed...
 
I know someone will probably want to hit me for saying this but to confirm. Are you on about proper Cats which I think where only fitted to the post 2007 Fenders or DPFs post 2002?

My dates may well be totally wrong.
 
I know someone will probably want to hit me for saying this but to confirm. Are you on about proper Cats which I think where only fitted to the post 2007 Fenders or DPFs post 2002?

My dates may well be totally wrong.

Here is the link for the MOT notice: https://www.gov.uk/government/uploa...ata/file/275427/mot-special-notice-1-2014.pdf

My local tester has seen it and tells me it applies to anything that was described as a catalytic convertor fitted at build. Yes it also includes DPF's.
The rule was brought in to stop the practice of removing DPF's, but it seems cats have also been caught up in the rule change.

I certainly pity anyone that needs to replace a DPF, could be a lot of scrapped cars.
 
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Cheers mate, so for all intensive purposes a DPF is a Cat and if fitted from factory is now required to pass the MOT.

Links broken.

Link works now.

The Cat's on TD5's and some 300 tdi's were single stage convertors. They were not DPF's as there was no means of regeneration when they blocked. In reality they do very little to the exhaust gases since the temp. of diesel exhaust is too low to effect good catalysis. So all they do is reduce power and cause turbo lag, probably resulting in increased fuel consumption that defeats the object of having them in the first place.
 
Hhm :scratching_chin:

Im sure they can't retrospectively do that. Needs more investigation.

I'm all for more investigation, but if the tester can determine that a Cat was fitted at build and is now absent, it will fail MOT. It isn't retrospective since the Cat shouldn't have been removed in the first place. It wasn't an option, but a requirement for whichever Euro emissions standard applied at the time.
 
hmmm seems interesting and odd. Either way it only takes 30 mins to change the pipe over if that. Going to leave mine without the 'Cat', MOTs in June so I shall see what the ole chap says, if it passes awesome if not then ill stick the 'Cat' back in.
 
Here is the link for the MOT notice: https://www.gov.uk/government/uploa...ata/file/275427/mot-special-notice-1-2014.pdf

My local tester has seen it and tells me it applies to anything that was described as a catalytic convertor fitted at build. Yes it also includes DPF's.
The rule was brought in to stop the practice of removing DPF's, but it seems cats have also been caught up in the rule change.

I certainly pity anyone that needs to replace a DPF, could be a lot of scrapped cars.

I know! My car is only worth £5k, I can't spend £1200+ on a new DPF...
 
I'm all for more investigation, but if the tester can determine that a Cat was fitted at build and is now absent, it will fail MOT. It isn't retrospective since the Cat shouldn't have been removed in the first place. It wasn't an option, but a requirement for whichever Euro emissions standard applied at the time.

yes but it would be the same for all modifications done to all cars.

The government can't suddenly turn around and say you will now fail the MOT if you don't have the same tyres or wheels that it left the factory with.

Its not an MOT fail at the moment to have different wheels and tyres and its not an mot fail on a diesel to not have a CAT.

Its all down to interpretation.

I have a classic mini that my wife took to MOT at the Saab main stealer she worked at. It failed as the seat is only bolted down in 2 places(it provides access to the rear).

I took the car for a re-test at my usual garage and he couldn't understand why the other chap failed it. Its how it left the factory and is a standard feature. Interpretation and understanding the flexibility is key.
 
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