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Remove cat.

  • helijohn
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10 Oct 2014 19:58 #126167 by helijohn
Replied by helijohn on topic Remove cat.

kirkynut wrote: Or just gut your current cat so it looks like it has one.

There are no exhaust limits on older jimnys specified for the mot so it gets tested by the old emissions test, which it ought to pass without a cat.

Kirkynut


Does this mean with an older Jimny that even when the CAT is worn out and knackered it will pass the MoT emissions wise?

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  • bikerjohn57
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10 Oct 2014 21:21 #126185 by bikerjohn57
Replied by bikerjohn57 on topic Remove cat.
On my 2004 O2 rag top (35K). the centre tube in the cat has collapsed, rattles like a bag of nails but emissions wise passed the MOT no problem.

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11 Oct 2014 08:36 #126201 by robs5230
Replied by robs5230 on topic Remove cat.
can anyone explain in simple terms, what the positives and negatives are if a cat is gutted but the sensor is still in place ? i have a 99 g13bb . cheers

standard jimny - for now

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11 Oct 2014 10:27 - 11 Oct 2014 10:30 #126211 by kirkynut
Replied by kirkynut on topic Remove cat.
I shall try to answer all your questions at once.

A Jimny with no cat or an ineffective worn out cat ought to pass an mot on emissions as long as the cat is not blocked and there's no other issue with the car like worn piston rings causing high emissions.

They are tested on the pre 1992 emissions figures because Suzuki didn't release emissions figures for the earlier Jimnys. This may be and is likely to be different for later cars, from when I don't know. Mine is a 2000 model.

Can an mot tester on here look jimny emissions up for us please.

The only thing is that although the emissions may be good enough for the relevant test the car knows that the emissions are not as good as they could be with a working cat so it pops on an engine management light with a code for bad cat efficiency. That light is an mot failure.

There has to visibly be a cat present for the mot and the light must not be on. The light has to come on and go out when the car starts too or you get an advisory which may be a fail if not fixed for next year. Ie: you can't just remove the bulb.

How hard can it be to make an led light for 5 seconds when fed an ignition only live though? I mean on it's own independent circuit to look like it's right. Maplins!

When my cat failed but did not get blocked I kept putting the light out for over a year before an un knowledgeable mot tester failed it on emissions. I went elsewhere for my mot the next year and my friend was the tester who told me that there was little chance of it passing the post 1992 test even with the new cat so he wouldn't bother but showed me as I expressed curiosity.

He told me that there were no figures for the Jimny so as long as it passed the pre 1992 emissions test it was fine.

It ran ok when the light was on. It was simply telling me that the emissions were high for a car that has a cat. If I had made sure that the light was out and taken it to him the previous year it would have passed and I wouldn't have paid for a new cat and would just keep putting the light out once a month.

Kirkynut

Disclaimer: This is knowledge I have picked up along the way which I believe to be true. I am not an mot man and have not studied the rules.

The underdog often starts the fight, and occasionally the upper dog deserves to win - Edgar Watson Howe.

My Jimny Thread Here: www.bigjimny.com/index.php/forum/8-my-ji...on-continues?start=0
Last edit: 11 Oct 2014 10:30 by kirkynut.
The following user(s) said Thank You: robs5230

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  • RichiesJimny
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11 Oct 2014 14:08 - 11 Oct 2014 15:41 #126222 by RichiesJimny
Replied by RichiesJimny on topic Remove cat.

kirkynut wrote: I shall try to answer all your questions at once.

A Jimny with no cat or an ineffective worn out cat ought to pass an mot on emissions as long as the cat is not blocked and there's no other issue with the car like worn piston rings causing high emissions.

They are tested on the pre 1992 emissions figures because Suzuki didn't release emissions figures for the earlier Jimnys. This may be and is likely to be different for later cars, from when I don't know. Mine is a 2000 model.

Can an mot tester on here look jimny emissions up for us please.

The only thing is that although the emissions may be good enough for the relevant test the car knows that the emissions are not as good as they could be with a working cat so it pops on an engine management light with a code for bad cat efficiency. That light is an mot failure.

There has to visibly be a cat present for the mot and the light must not be on. The light has to come on and go out when the car starts too or you get an advisory which may be a fail if not fixed for next year. Ie: you can't just remove the bulb.

How hard can it be to make an led light for 5 seconds when fed an ignition only live though? I mean on it's own independent circuit to look like it's right. Maplins!

When my cat failed but did not get blocked I kept putting the light out for over a year before an un knowledgeable mot tester failed it on emissions. I went elsewhere for my mot the next year and my friend was the tester who told me that there was little chance of it passing the post 1992 test even with the new cat so he wouldn't bother but showed me as I expressed curiosity.

He told me that there were no figures for the Jimny so as long as it passed the pre 1992 emissions test it was fine.

It ran ok when the light was on. It was simply telling me that the emissions were high for a car that has a cat. If I had made sure that the light was out and taken it to him the previous year it would have passed and I wouldn't have paid for a new cat and would just keep putting the light out once a month.

Kirkynut

Disclaimer: This is knowledge I have picked up along the way which I believe to be true. I am not an mot man and have not studied the rules.


I'm not sure where your tester gets his info from but if you follow the flow charts it clearly states if you cannot find an exact match in the emission data base carry out the emission test to default limits.
So all jimny's must pass an emission test. :)

The engine management light is not part of the test and any advisory items are purely advisory it doesn't mean you must fix them.

All the test manuals are on line now but you must read them very carefully
www.motinfo.gov.uk/htdocs/m4s07000309.htm
www.motinfo.gov.uk/htdocs/m4s07000311.htm
Last edit: 11 Oct 2014 15:41 by RichiesJimny.

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11 Oct 2014 15:37 - 11 Oct 2014 15:49 #126226 by Rhinoman
Replied by Rhinoman on topic Remove cat.

kirkynut wrote: They are tested on the pre 1992 emissions figures because Suzuki didn't release emissions figures for the earlier Jimnys. This may be and is likely to be different for later cars, from when I don't know. Mine is a 2000 model.


No, it has to pass the default 'cat test'

When removing the cat the rear O2 sensor is usually spaced up out of the direct flow of the exhaust gasses.

Some Suzukis and a bunch of motorcycles.
Last edit: 11 Oct 2014 15:49 by Rhinoman.

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