Sports cat MOT fail

[Henz]

As above, my Cooper S failed on the emissions last week. Only had the sports cat fitted in the last year so not something I've ever had to mess about with and rather naively I just rocked up with it rather cold.

Taking it back for the retest and will aim to get it nice and hot - what's the best sort of run to give it? A 30min jaunt down the motorway, then to the mot station and straight on for the test? Does a cat cleaner benefit at all?

Cheers...

[Krikkit]

Did they give you the fail sheet?

If you want to spank it then plenty of revs is the best way to get it good and hot.

[anonymous-user]

Was it an ebay special sports cat?

[stevieturbo]

Nobody can give any advice without the full emissions test sheet and reason for fail

[Henz]

It was a Cobra 200 cell sports cat and from my research did seem pretty confident it would pass the MOT.

st at uploading pics - is this enough detail from the fail sheet for the fast idle test?

Run 1
CO - 1.760 Vs max limit 0.200
HC - 621 Vs max limit 200

Run 2
CO - 0.884 Vs max limit 0.200
HC - 430 Vs max limit 200

Cheers...

[paddy1970]

With these numbers, I think you will have to light a fire underneath this car to get it to pass an MOT.

[norm4n]

My 2002 supercharged S has a Janspeed manifold and sports cat, it’s flown through MOTs for years. Give it a good thrashing on the way there

[Henz]

paddy1970 said:

With these numbers, I think you will have to light a fire underneath this car to get it to pass an MOT.

They did look grim even to my layman eyes. As a bit of background, the car hadn't been driven for weeks and I'm 5 mins away from the MOT station. I'm hoping that it looks particularly bad as it was probably stone cold at the time.

[Welshbeef]

Henz said:

It was a Cobra 200 cell sports cat and from my research did seem pretty confident it would pass the MOT.

st at uploading pics - is this enough detail from the fail sheet for the fast idle test?

Run 1
CO - 1.760 Vs max limit 0.200
HC - 621 Vs max limit 200

Run 2
CO - 0.884 Vs max limit 0.200
HC - 430 Vs max limit 200

Cheers...

Those emissions are terrible. Do you have the original to retrofit - and leave on due to the impact your car is having ?

[Henz]

Welshbeef said:

Those emissions are terrible. Do you have the original to retrofit - and leave on due to the impact your car is having ?

Not entirely convinced it's just the sports cat as my mods are very standard fare and they don't seem to cause issue for most.

How much impact is it having? I'd be very impressed if you can answer that considering you have zero idea what the car actually does (or doesn't which is entirely more appropriate).

[stevemcs]

My Cooper S has a Milltek 200 cell, i have to get it roasting hot and go straight to the emissions test.

[stevieturbo]

Henz said:

It was a Cobra 200 cell sports cat and from my research did seem pretty confident it would pass the MOT.

st at uploading pics - is this enough detail from the fail sheet for the fast idle test?

Run 1
CO - 1.760 Vs max limit 0.200
HC - 621 Vs max limit 200

Run 2
CO - 0.884 Vs max limit 0.200
HC - 430 Vs max limit 200

Cheers...

If it is in any way a modern standard car, something is seriously wrong. Fix the problem first before worrying about the cat. As presumably it is not a proper classic Mini Cooper you are referring to and you've fitted a cat to it.

Even if the cat was doing nothing at all, or no cat...the emissions should not be that bad.

[Zener]

A working cat wont pull 1.7 CO into VOSA requirments sort your fueling out etc first , HC is way off this is engine related not cat at this stage / those readings

[Henz]

Cheers both, that's really handy thanks

[E-bmw]

Henz said:

my mods are very standard fare and they don't seem to cause issue for most.

Can you be more specific as to the full list of mods here?

It will give us a much better chance of advising correctly.

Also, which S is it?

[georgeyboy12345]

Curious to know how you got on Henz

[eliot]

I think my twin turbo 5.7 chevy without cats or even closed loop lambda pulled better figures than that.

[Henz]

georgeyboy12345 said:

Curious to know how you got on Henz

The thrilling conclusion....

I decided to take it back for the free retest but give it a good hard run beforehand to get a hot reading. It was stone cold on the first test and thought it might be useful info to give to my mechanic.

Was pretty shocked when it actually passed, albeit very much at the limit.

[Zener]

Cold/warm engine would explain a lot small wonder it was failing glad you got it sorted however

[Henz]

Zener said:

Cold/warm engine would explain a lot small wonder it was failing glad you got it sorted however

Was lucky that I called at a quiet time. I got one of the mechanics who said to to bring it down and he'd guarantee it would get straight on.

Amazed it made that much difference...still wonder if there is an underlying issue but at least I can now get it to my mechanic under its own steam as the MOT was in its last days.