Cats on Diesels - pullgees
This may sound a dumb question but are catalytic converters fitted on diesels? Do they still cost a packet to replace?
Cats on Diesels - Group B
Yes modern diesels have them but for most cars they are now a lot cheaper than they used to be. My Dads first car with a cat was an early '90's Rover 820Si (petrol) and I remember him being told that if the cat went is was £1000 for a new one!
Just Googled it and found this place that does some diesel ones for under £200: www.cats4less.co.uk/home.php . I dont know what a genuine one from a main deaqler would cost?

I've heard of people with diesels removing the innards of their cat to give less exhaust back pressure. But its obviously less environmentally friendly. The MoT for diesels currently only checks for smoke, unlike the petrol engine test it doesn't check levels of HC, NOx etc.
Cats on Diesels - jc2
On early diesels(90s)they were fitted just to look "green" and had litte effect-some cars had cats in one country and straight thro' pipes in the neighbouring country.However with St.III & IV emissions they are most certainly effective and are fitted much closer to the engine-so they run hotter.
Cats on Diesels - pullgees
On early diesels(90s)they were fitted just to look "green" and had
litte effect-some cars had cats in one country and straight thro'
pipes in the neighbouring country.However with St.III & IV emissions they
are most certainly effective and are fitted much closer to the
engine-so they run hotter.



Ah that would explain why I saw a Citreon ZX (95) advertised with a cat. As I'm looking for a 90s diesel I should expect some to have cats then. But if they were not mandatory back then would it be mandatory to replace like with like today should the cat go?
Cats on Diesels - ziggy
Oxidation catalyst and EGR is pretty much standard.

They are not generally as problematic as petrol cats.
Cats on Diesels - DrS
Are cats on modern Diesels not mainly for getting rid of particulates? (Oxidation of soot)?
Surely no point in recirculating CO2?
Cats on Diesels - jc2
No.
Cats on Diesels - Group B
Are cats on modern Diesels not mainly for getting rid of
particulates? (Oxidation of soot)?
Surely no point in recirculating CO2?


Oxidation cats on diesels reduce CO and HC but don't reduce NOx. AFAIK particulate traps are a seperate thing and only recently been introduced for Euro IV emissions compliance.
Cats on Diesels - Phil I
Mine have no preference at all. Merely insist on warm bonnets. Will sleep on either.

Phil I
 

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