2000 Legacy B4 Emissions
Discussion
Magic beans always worked for me 
However, if you can't find any of those then a new cat would very likely guarantee a pass after it's had maybe 1000miles put on it beforehand. A remap though would not just get your car running nice but you could get the tuner to calibrate your fuelling and ignition timing tables to run that bit leaner where they correspond to idle and very low static loads up to 2500rpm (which is the max rpms stationary they use when checking your emissions).
Equally, it might have made a difference to the emissions test if the car had been taken for a good hard run just beforehand to heat your cat converter up which may well have then put your car well inside the test limits rather than right on the edge.
ETA: Charlie is also right it could have been either of those too but a tuner could also recalibrate your MAF sensor even if it's a bit out to help with fuelling at idle and low loads up the rpm scale.
However, if you can't find any of those then a new cat would very likely guarantee a pass after it's had maybe 1000miles put on it beforehand. A remap though would not just get your car running nice but you could get the tuner to calibrate your fuelling and ignition timing tables to run that bit leaner where they correspond to idle and very low static loads up to 2500rpm (which is the max rpms stationary they use when checking your emissions).
Equally, it might have made a difference to the emissions test if the car had been taken for a good hard run just beforehand to heat your cat converter up which may well have then put your car well inside the test limits rather than right on the edge.
ETA: Charlie is also right it could have been either of those too but a tuner could also recalibrate your MAF sensor even if it's a bit out to help with fuelling at idle and low loads up the rpm scale.
Edited by ScoobieWRX on Monday 26th November 22:07
There are many tuners that will travel to NI from England, you just need to find one that will do it but it won't be cheap because you have to pay their travel costs as well as the remap. There may well be one in NI but i don't know of one. Next best option is you come to England and have it done here that way apart from your own travel costs there is just the remap to pay for.
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