emissions light after fitting new cat..

[huckin18]

right old cat had a huge hoel in it before it entered the cat... no emissions light appeared but sounded gash and went even worse... so
fitted a new cat (proper one not sports) and hey presto the emissions light appears and wont go away... also fitted a gdi exhaust at the same time...
172 on a 52 plate any ideas? new lamba (i think) sensor? its not blowing from anywhere? is it possible to disconnect the sensor or do i just need to reset it? help appreciated!
planning on selling the car so the dash looking bright and colourful might not help...

 

[mark.k@GDI]

needs codes resetting fella, try the free disconnecting the battery trick for half hour and then start it an let it idle for 5 mins. if that doesn't work then a scanners gonna be needed!!

 

[huckin18]

thanks mate will try t bat tomorrow morning see what happens!
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