Diesel decats to fail MOT

[r44flyer]

Can't remember reading this anywhere before until it was posted on another forum today. If it's a repost I apologise.

From 16th Feb diesel powered vehicles will be subject to a check for the presence of catalysts AND particulate filters and will fail if either are not present where one was fitted as standard.

[Toaster Pilot]

People made a big fuss about DPFs but nobody mentioned cats - useful to know.

[r44flyer]

Toaster Pilot said:

People made a big fuss about DPFs but nobody mentioned cats - useful to know.

Indeed. So far no one has been worried as diesels have not been subject to an emissions test, only a smoke test, which they can easily pass despite having no cat. As a popular performance modification for diesels I can see a lot of people getting caught out by this come MOT time.

[Toaster Pilot]

I imagine it's a common way to avoid paying for a replacement cat too - I'd have thought about that if the one on my crusty old Felicia had given up!

[C.A.R.]

Buggeration.

I fitted a decat pipe for the performance benefit and the old one had a hole in. It seemed pointless spending £100+ on a 13 year old car for a pattern cat.

I'll have to see if someone can just weld a cat housing over the top of the pipe. They only check for the presence - not whether it's actually functioning!

[r11co]

Interestingly (and I am sure this has been mentioned elsewhere) it does not say that the cat/DPF has to be functioning, so presumably the previous emission standards are all that apply as far as this is concerned.

So, if an evacuated or non/malfunctioning cat/DPF cannister is present as per the strict interpretation of the regulation the car still passes this requirement.

[Mikeyplum]

Great news

Literally ordered a SS Decat yesterday

Ahh well, got a year to sort something out.

[kambites]

r11co said:

Interestingly (and I am sure this has been mentioned elsewhere) it does not say that the cat/DPF has to be functioning, so presumably the previous emission standards are all that apply as far as this is concerned.

So, if an evacuated or non/malfunctioning cat/DPF cannister is present as per the strict interpretation of the regulation the car still passes this requirement.

It depends on exactly how you word the question - modification of a car in such a way that it would fail the emissions part of the type approval test that it was put through when originally released has always been illegal; so a nun-functional cat or particulate filter has almost certainly always been illegal (as, I suspect, are many remaps). The new testing, however, will probably still not entirely enforce the regulations so you'd probably get away with a cat body with no internals.