HELP!!!really bad MOT co emmisions fail

[rusty bolts 0]

hi there help needed, lol

i have a 95 rado 2.0 8v had mot today and faild badly on emmisions COs was running near on 4%, i only bought the car 7 months back, all i have done since then is induction kit and stainless exhaust now with cat back on for mot! i really dont know what could be the cause! one thing i was wondering now i have induction rather than air box, it is right to seal off the vacum hoses? ive also heard about an ECU reset whats the best way to do it, and could that be a possible cause? ive convinced the mot guy to do a none cat test but still it runs too high even at idle. what can i do short of bribing him wit a big wod of cash lol any help will be much appreciated :)

cheers in advance james

[davidwort 0]

get it scanned for fault codes, could be the lambda probe is shot.

[dr_mat 0]

Typical when removing/refitting exhausts is to knock the lambda around, so that's absolutely the most likely problem. The lambda will be fitted in the CAT pipe, just before it. If it's damaged the car will typically overfuel like buggery and produce black smoke a lot .. Fuel economy will be appalling too.

[rusty bolts 0]

thanks for the help guys, vag com is all clear. lambda sensor should be ok because i took it off before roving exaust! but i will check it i have a spare one from the decat pipe! im not sure weather it is the lambda cos ther is no black smoke at all and fuel eco seams to be fine!another thought im not sure when she last had an oil change could fuel in the oil make such a bad failure? i dunno, i jst heard on another post fuel in the oil makes bad Co readings.