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Matt
Matt, Mechanical Engineer
Category: Car
Satisfied Customers: 22168
Experience:  BEng hons Mech engineering, in auto industry 22 years
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We have a Fabia mk2. Having removed the front cat and

Resolved Question:

We have a Fabia mk2. Having removed the front cat and replacing the rear one the engine management light has now come on. Do you think the two things are related
Submitted: 3 months ago.
Category: Car
Expert:  Matt replied 3 months ago.

hello

If you have removed the front cat and not changed the ECU flash calibration then yes you'll get a check engine light as the O2 sensors in the exhaust will be showing the exhaust emissions are well out of range

so if this is a track car where you don't have to run the cat then you'll need an ECU calibration change to over come this

however a road car MUST have a cat or you're breaking the law and it certainly won't pass the MOT

can I ask why you have removed it?

Customer: replied 3 months ago.
It is my sons car and he is not exactly flush with money. The mechanic who did it seemed to think it would run ok. It does sound a bit noisier now. Should we pay up and replace the front cat ?
Expert:  Matt replied 3 months ago.

Hello

if the front cat was clogged / broken up then this can really hurt engine power so you sometimes remove the cat as part of the diagnostic process

but you do need a cat

how about a good used item?

http://www.ebay.co.uk/itm/SKODA-FABIA-1-4-PETROL-MANIFOLD-CAT-CATALYTIC-CONVERTER-036131703G-08-14-BXW-/112144238442?fits=Car+Make%3ASkoda%7CModel%3AFabia%7CCars+Year%3A2008&hash=item1a1c51476a:g:2G0AAOSwPCVX4pnT

Customer: replied 3 months ago.
i will look for one and get it fitted as soon as possible. Thanks for your help Matt
Expert:  Matt replied 3 months ago.

no problem

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