Scoob just failed MOT on emissions (carbon monoxide and hydrocarbon content) and lambda reading!

Have a blitz nur spec turbo back system and wasn't aware it was decatted, and as I bought the car with this on, i don't have the original exhaust to put back on.
Would it pass with only one cat? and if so can i get away with just replacing the downpipe? seen this: *SUBARU IMPREZA WRX STI EXHAUST DOWNPIPE WITH CAT * on eBay (end time 01-Oct-09 11:57:41 BST)

any help appreciated!
Cheers!

 

Yes it should pass with only the downpipe cat fitted

 

Nice one cheers mate!

 

Could it not be that the lambda its self is fudged, hence its running rich??

Cheaper than a new cat!

 

yeah could be that too, but from what i've read on here i think you still defo need a cat! bought it now anyway so will soon see! fingers crossed! cheers for the advice tho!

 

No probs mate.

They can be a pain to do, this thread may be of help when the time comes to swap it

https://www.scoobynet.com/general-te...ull-decat.html

 

defo cat needed ' i run a mot station and if you have'nt got a cat fitted the readings will be way out on fast idle test. all you need is a down pipe cat , can i suggest putting a fast flow sports cat on it due to if it's been mapped without cat you might have prob's with the performance , but if you put a fast flow cat on the car will pass mot and you should still have same vroom vroom

 

thanks for the advice, am defo of thinkin of goin down the sport cat route-bit tight on cash atm so just need to get it thru the MOT for the moment. The downpipe just came through today so gonna tackle it saturday morning, nice one for the warning about the hard to reach nut will take some preparatory measures tonight with a bit of wd and shall purchase a UJ socket to try and save a bit of headache!