Sorry I should have specified it's a S3
That's exactly what I was thinking, no cat would be instant fail. The and has been altered now, comments about passing mot with Decat have been removed. I'll give this one a miss anyway.I failed (didnt pass) an MOT recently due to having an APR sportcat fitted. I told Audi the car had to be driven to get it nice and hot. With just the car statically up to temp it failed emissions. Had to be taken out twice for a spirited run to pass emissions. I'd expect a decat to fail especially if it Audi whos MOTing.
'Fell off' PMSL!From my own records: I had been running my own Audi 8P RS3 from near new with secondary catalytic by-pass pipes, both the noise and engine response I though better.
On 30 Aug 2014 @ 8213 miles, my AUDI dealer (Stafford Audi) offered me a pre-MOT and Service Check and this was duly undertaken by a technician who was a non-authorised MOT inspector. The measured CO was 0.02% and, as far as Stafford Audi was concerned, the car was a 100% pass!
However, on 12 Sept 2014 @ 8667 miles I presented my car just the same i.e., sans cats for its 3rd service and 1st MOT. Arriving home a telephone call from an apologetic Stafford Audi informed me my car would FAIL due to the missing secondary catalytic converters. The resolution offered and accepted was that they would send a driver to collect my secondary catalytic converters, fit them, MOT the car, and re-fit the secondary catalytic by-pass pipes should I desire - all free of charge of course.
Offer accepted and with the secondary catalytic converters fitted, the CO was 0.01%
So with @ 0.01% CO. Without @ ,0.02% CO. In addition, the pass limit is 0.20% CO.
Needless to say and if only to re-evaluate the car with secondary cats I drove home with 'em fitted only to refit the by-pass pipes a couple of days later.
Since September 2014, my secondary catalytic converters have remained safely in my loft and my car goes for MOT elsewhere.
Note: Miltek put these on their secondary catalytic by-pass pipes just to cover their own backsides:
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Mine 'fell' off
'Fell off' PMSL!