MOT with Decat

robsy

Registered User
So there's a car for sale and the owner has stated it passed MOT with no issues even with a Decat. Is that possible on the 8v? Does it have multiple cats. As far as I was aware if you remove a cat then it's an instant MOT failure.
 

T-1000

Registered User
Sorry I should have specified it's a S3

When I had my 8P RS3 I had it tested standard then with The secondary cats removed and there was barely any difference in the reading the mot guy told me.

If a tester is keen though he should be looking for them visually under the car, so could still fail the car, depending on where you go.
I’d imagine an Audi MOT tester will fail it visually.

If you remove the primary cat then I’d imagine it will fail.

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rafletcher

Registered User
Cat removal (unlike DPF removal) isn't an MOT failure. The risk is that cat removal / fitting hi-flow cats MAY cause your car to exceed the emissions limits, which is an MOT failure. A lot of people advise finding a "friendly" MOT tester to do de-catted vehicles.
 

CanadaA3wales

Canadian living in South Wales - Audi A3 8V 150BHP
My MOT guy/friend said to just cover it as they are no longer allowed to take anything off the vehicle, so if they cant see it, they cant remove it.
I was shocked when I had 2 wheel bolts missing on 1 wheel when I bought the car, but he said as I have caps on them, they would not be allowed to remove them, he hates the current MOT system as he could be sending out dangerous cars, but there is nothing he can do.
He said I can take the DPF off and cover it, but if it fails the emmisions then your stuck spending the money to put a new one on.
 

Leevr

Registered User
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.
 

robsy

Registered User
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.
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.
 

45bvtc

The Older I Get The Better I Was
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Column 3 (Reason for rejection) item 3 (A catalytic converter missing where one was fitted as standard) is why NOT to take a modified AUDI exhaust system to an AUDI dealer for MOT:

MOT cats.JPG
 

45bvtc

The Older I Get The Better I Was
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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:

Not for road use.jpg


Mine 'fell' off :yahoo:
 
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pburv

Registered User
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:

View attachment 209606

Mine 'fell' off :yahoo:
'Fell off' PMSL!
 

45bvtc

The Older I Get The Better I Was
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Gold Supporter
'Fell off' PMSL!

Unfortunately for Stafford Audi Paul when a tad younger and still in employment one of my roles was as Chief Engineer for a motor vehicle manufacturing facility and one responsibility was for Motor Vehicle Type Approval and Compliance to: Council Directive 91/441/EEC of 26 June 1991 amending Directive 70/220/EEC on the approximation of the laws of the Member States relating to measures to be taken against air pollution by emissions from motor vehicles :readit:

For me anyone taking a motor vehicle for MOT test these days with an exhaust system that does not comply (i.e., modified) with that particular vehicles Type Approval Registration (e1*2007/46*0615*01 for the 8P RS3) should not be surprised if the vehicle FAILS but then pleasantly surprised and happy even if and when it passes as does my own 2011 AUDI 8P RS3, 3380 H, and it just did, again:

RS3 MOT.JPG


ALL, except the first - see #12 above, with Miltek secondary catalytic by-pass pipes fitted but NOT tested at an AUDI dealer :thumbs up:

Apologies for BLUEY's mileage but our SQ5 sure takes some beating and even more so now that 034 ARB has been fitted :racer:
 
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45bvtc

The Older I Get The Better I Was
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I think you need to apologize for the rather long 'directive' title. Jeez! try saying that after a few. lol:readit:

I was younger then Paul, it was so much easier; like I say, "The Older I Get The Better I Was"
 
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