De-CAT potential problems.

Phil

Guest
Firstly, I hope this is in the right place - I find there are too many forums and sub-forums on here!

I want to De-CAT my 1.8T Octavia. I've asked about potential problems on Briskoda.net but there doesnt seem to be a clear answer.

If I cut out the CAT and replace the CAT with a clear pipe section, I believe the vehicle will just scrape through the MOT emissions test, however, I am expecting problems with the lambda sensors giving confusing signals to the ECU.

Has anyone had any experience of de-CATing a 1.8 20VT ?
 

m0rk

sarcasm comes free
Staff member
May 19, 2001
27,787
33
Clanfield, UK
It won't pass an MOT without a cat - no chance at all.

You will have a MIL light as well, unless you run Revo Stage 2 code which ignores the cat failure Lambda code
 

Phil

Guest
I know someone with a Jabba remapped Octavia that has got a car through an MOT without the CAT. Apparently it is on the edge though and you must ensure the climate control is switched off.
 

Feel

Veedubya 'velle
Jun 12, 2003
4,918
2
Midlands
No direct experience but: I doubt you'll pass emissions, you might scrape through, but I doubt it.

Unless you run a remap that disables the second lambda sensor you will get a light on the dashboard and a fault code logged that tells you that your cat is below efficiency (i.e. that it has failed),

Edit: Must type faster
 
Last edited:

m0rk

sarcasm comes free
Staff member
May 19, 2001
27,787
33
Clanfield, UK
Phil said:
I know someone with a Jabba remapped Octavia that has got a car through an MOT without the CAT. Apparently it is on the edge though and you must ensure the climate control is switched off.


Seriously - you won't - it's the fact that the emissions that the cat 'catches' the level is so low that it'll detect there is no cat.

why not just buy a sports cat?
 
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