Catalysts on diesels - Robble
Hi,

I have a 1995 VW Golf TDi.
The exhaust has blown in several places including the catalytic converter. Having a new cat fitted costs £260 plus the cost of the rest of the exhaust.
I have a couple of questions. Firstly, does my car need to be fitted with a cat by law and would removing it and replacing it with a length of pipe cause it to fail the MOT on emissions or be illegal?
(My friend's V-reg Saxo diesel doesn't have a cat fitted)
Secondly, would removing the cat be detrimental to the performance/economy of the car. I've heard that it might confuse the ECU and give poor acceleration and economy.

Any thoughts?
thanks
Rob

Catalysts on diesels - Andrew-T
I don't think a 95 diesel required a cat by law, but an expert will be along shortly .. ..
Catalysts on diesels - glowplug
Have a look around this site, I'm not sure if it can answer your question directly but may give you some idea.

www.tdiclub.com/

Steve.
Catalysts on diesels - Pete F
You won't fail the MOT by removing the cat. Neither will it confuse the ECU because there is no feedback from the cat to the ECU. German makers tended to fit cats on Diesels because it was a market (i.e. customer) requirement. The difference they make on earlier Diesel emissions is small.
Catalysts on diesels - jc
Small effect,actually negligible but customers wanted to feel green;many of them removed their catalysts and only refitted them for the TUV(mot)test or when selling but modern St.III/IV calibrations do need catalysts.
Peugeot 406 Catalyst Matrix Breakup - GolfR_Caravelle_S-Max
** NEW QUESTION**
Further to the Cam Belt breaking, this morning, I had an MOT (1 week 2 days after the Cam broke and was repaired... see the "Cam belt Gone.. thread)

It failed. Only on a holy exhaust (god bless it)
But they heard the noise I mentioned, and said the Cat was "rattling" inside...

OK. Does not require doing, but I will get it cut out in due course...

However, 1 mile up the road, someone rear-ended me, hitting the Exhaust (Paint on it), badly scuffing the bumper, and folding their megan bonnet and demolishing their bumper...

The cat sounded a LOT worse after this untimely incident...

** My Question:
The Exhaust place will not "cut out" the cat and "weld in" a pipe as it's curved and "no-one can bend a pipe" but will "scrape out" the cat and replace the middle box section.

The cat is not needed for MOT (Smoke test only although it passed on emmissions with 1.24m-1 (Max limit is 3.00)) but the Garage said "oh, if the cat is removed and not replaced with like-for-like, the cams will sieze because of overheating"

sounds like PFD's to me.. (koi "pink fluffy die")

I've gone for the "scrape and middle box (and front connection unit)" and hope cat will be ok when empty...

** presumably it may be more noisy?

re: insurance, I will only be claiming for the scrapes down to the black plastic (on a colour coded bumper)
** (paint master?)

thx.
alfa pug.
The Garage (one I have not used before)
Peugeot 406 Catalyst Matrix Breakup - DL
I'd rather remove the catalyst altogether - the empty 'box' can cause some resonance at certain revs.

Otherwise, you'll have no ill-effects whatsoever.

The cams have no connection with the catalyst - that is pure drivel!
--
groups.msn.com/honestjohn/problems.msnw?Page=1 - Pictures say a thousand words.....
Peugeot 406 Catalyst Matrix Breakup - GolfR_Caravelle_S-Max
thanks for the reply.
thought it was BS.

garage "can't get someone to bend a pipe".. Guess I'll get an engineering co. to do it then.

All the other garages and "exhaust centres" (no names mentioned) would only replace the cat with another one, not a cut-and weld job.... where's the british innovation and ingenuity gone?
Peugeot 406 Catalyst Matrix Breakup - John S
'No-one can bend a pipe'. How the heck are exhausts made then?
Peugeot 406 Catalyst Matrix Breakup - DL
I guess it all comes down to "Being bothered"

Having the correct equipment [or access to..] is half the battle, the will to help the customer out is the other half!

It's a shame it appears to be a dying trend.
--
groups.msn.com/honestjohn/problems.msnw?Page=1 - Pictures say a thousand words.....
Peugeot 406 Catalyst Matrix Breakup - madf
to be fair, bending large diameter pipework does require specialised equipment and mandrels.. having said that they appear to be full of carp.

Why not get one of the many exhaust specialists to fit an aftermarket cat? They cost between 30 and 50% of the cost of the OE.

madf


Peugeot 406 Catalyst Matrix Breakup - GolfR_Caravelle_S-Max
Front fitting kit fitted, cat "scraped out", new centre Box section fitted. ... MOT passes. Car feels like a new car. Pulled away and torque (on a dry, 6 degree centigrade road) spun the wheels in second. I guess "clinker" from cat was obstructing the baffles. Amazing.
New lease of life at 180k!
 

Ask Honest John

Value my car