MOT secondary decat
Discussion
I've got three cats on my car, well had, I have two now.
I did some reading before misplacing two and I'm pretty sure it's legal and will pass an MOT, providing the emissions are ok. But a local garage has told me it would fail as a factory fitted cat is missing.
Is anybody here a technically good MOT'er and know for sure? And if I have interpreted correctly, how I go about telling a garage that they can't fail my car for it without getting punched of failed for something random.
MOT manual: https://www.gov.uk/government/uploads/system/uploa...
7.1.3
A failure for this section is the bit about factory fitted cats missing, but I do not believe my 2010 car is subject to a "full catalyst test".
Looking at 7.3.C are some pretty flow charts.
If you follow it through, a non-gas car first used after 1992 needs a basic-emissions-test. Some cars have explicit entries with non-standard emissions, but my car isn't listed in that list (https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/542070/in-service-exhaust-emission-standards-for-road-vehicles-18th-edition.pdf), or the 19th edition draft update.
I know that my car will pass an emissions test without the secondaries.
Is my reading correct and my local garage talking bs? Or am I way off mark?
I did some reading before misplacing two and I'm pretty sure it's legal and will pass an MOT, providing the emissions are ok. But a local garage has told me it would fail as a factory fitted cat is missing.
Is anybody here a technically good MOT'er and know for sure? And if I have interpreted correctly, how I go about telling a garage that they can't fail my car for it without getting punched of failed for something random.
MOT manual: https://www.gov.uk/government/uploads/system/uploa...
7.1.3
On spark ignition engine vehicles that qualify for a full catalyst emissions test and all compression ignition vehicles check the presence of catalytic converter(s) and particulate filter(s).
Note: To ascertain whether a spark ignition engine vehicle qualifies for a full catalyst test, use the flow charts in Section 7.3.C disregarding the result of the Basic Emissions Test.
A failure for this section is the bit about factory fitted cats missing, but I do not believe my 2010 car is subject to a "full catalyst test".
Looking at 7.3.C are some pretty flow charts.
If you follow it through, a non-gas car first used after 1992 needs a basic-emissions-test. Some cars have explicit entries with non-standard emissions, but my car isn't listed in that list (https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/542070/in-service-exhaust-emission-standards-for-road-vehicles-18th-edition.pdf), or the 19th edition draft update.
I know that my car will pass an emissions test without the secondaries.
Is my reading correct and my local garage talking bs? Or am I way off mark?
-Dash- said:
a local garage has told me it would fail as a factory fitted cat is missing.
I will leave the legal interpretation to the experts, but obviously nothing you say is going to convince that particular local garage that the vehicle can pass the MOT test, now they have decided their position. If I were you, I'd try getting it tested at a couple of other test stations and see whether they have the same view. What I would NOT do, is ask them in advance whether removal of a cat would be a reason for them to fail it.Your garage isn't talking BS at all, you have removed cats, your car is post 1994 & therefore for you to remove the cats you have made your car illegal & therefore not able to pass an MOT based on the principle that you have removed/disabled part of the emission control system.
However, as has been pointed out above not everyone sees it that black/white.
However, as has been pointed out above not everyone sees it that black/white.
E-bmw said:
Your garage isn't talking BS at all, you have removed cats, your car is post 1994 & therefore for you to remove the cats you have made your car illegal & therefore not able to pass an MOT based on the principle that you have removed/disabled part of the emission control system..
Such an authoritative statement, would you mind citing the regulation that mandates that? Given that as per my original post referencing the current MOT manual, I can't find anything (as part of the MOT and not C&U) that requires all cats to be present at all providing that the vehicle can pass a BET.By "full cat test", it means as opposed to a non-cat test - it even says "ignore the BET bit".
It might pass the emissions, but... 7.1.3
https://www.mot-testing.service.gov.uk/documents/m...
It might pass the emissions, but... 7.1.3
https://www.mot-testing.service.gov.uk/documents/m...
E-bmw said:
Your garage isn't talking BS at all, you have removed cats, your car is post 1994 & therefore for you to remove the cats you have made your car illegal & therefore not able to pass an MOT based on the principle that you have removed/disabled part of the emission control system.
However, as has been pointed out above not everyone sees it that black/white.
Except he does still have a cat fitted, and his car most probably will still pass the emissions test to prove it is fully functional as the test demands.However, as has been pointed out above not everyone sees it that black/white.
TooMany2cvs said:
By "full cat test", it means as opposed to a non-cat test - it even says "ignore the BET bit".
It might pass the emissions, but... 7.1.3
https://www.mot-testing.service.gov.uk/documents/m...
No it doesn't? It says:It might pass the emissions, but... 7.1.3
https://www.mot-testing.service.gov.uk/documents/m...
"On spark ignition engine vehicles that qualify for a full catalyst emissions test..."
Hmm, how do we know what qualifies for a full catalyst test?
Oh yeah, it says below:
"To ascertain whether a spark ignition engine vehicle qualifies for a full catalyst test, use the flow charts in Section 7.3.C"
So 7.3 page 6 covers the non-CAT test, but for sake of argument, lets assume this applies to a CAT vehicle.
Post 1992 vehicle not using gas - carry out BET.
If we assume this doesn't apply we look at the next flow chart, on page 8. Vehicle first used after 1992? Yes. Carry out BET.
Only then if it fails BET do you need to go on and do other things, such as a full catalyst check or vehicle specific lists.
So according to the flow charts, the vehicle (and frankly, most modern vehicles) don't qualify for a full catalyst test. And as a result, we don't need to "check the presence of catalytic converter(s) and particulate filter(s)".
I'm happy to be shown where that is not correct, but so far I've just found people on the Internet stating "it's illegal" without actually providing any backing to that.
-Dash- said:
No it doesn't? It says:
"On spark ignition engine vehicles that qualify for a full catalyst emissions test..."
Hmm, how do we know what qualifies for a full catalyst test?
Oh yeah, it says below:
"To ascertain whether a spark ignition engine vehicle qualifies for a full catalyst test, use the flow charts in Section 7.3.C"
So 7.3 page 6 covers the non-CAT test, but for sake of argument, lets assume this applies to a CAT vehicle.
Post 1992 vehicle not using gas - carry out BET.
If we assume this doesn't apply we look at the next flow chart, on page 8. Vehicle first used after 1992? Yes. Carry out BET.
Only then if it fails BET do you need to go on and do other things, such as a full catalyst check or vehicle specific lists.
So according to the flow charts, the vehicle (and frankly, most modern vehicles) don't qualify for a full catalyst test. And as a result, we don't need to "check the presence of catalytic converter(s) and particulate filter(s)".
I'm happy to be shown where that is not correct, but so far I've just found people on the Internet stating "it's illegal" without actually providing any backing to that.
For the mot cars with cats will go through a basic emissions test, if it passes that a full test is not required. If it fails a full longer emissions test is undertaken to see if it can pass that, if not it fails."On spark ignition engine vehicles that qualify for a full catalyst emissions test..."
Hmm, how do we know what qualifies for a full catalyst test?
Oh yeah, it says below:
"To ascertain whether a spark ignition engine vehicle qualifies for a full catalyst test, use the flow charts in Section 7.3.C"
So 7.3 page 6 covers the non-CAT test, but for sake of argument, lets assume this applies to a CAT vehicle.
Post 1992 vehicle not using gas - carry out BET.
If we assume this doesn't apply we look at the next flow chart, on page 8. Vehicle first used after 1992? Yes. Carry out BET.
Only then if it fails BET do you need to go on and do other things, such as a full catalyst check or vehicle specific lists.
So according to the flow charts, the vehicle (and frankly, most modern vehicles) don't qualify for a full catalyst test. And as a result, we don't need to "check the presence of catalytic converter(s) and particulate filter(s)".
I'm happy to be shown where that is not correct, but so far I've just found people on the Internet stating "it's illegal" without actually providing any backing to that.
If you look under 7.1.3 reasons for rejection, a car can be rejected where a cat has been removed where it was originally fitted as standard. If the removal is obvious visually then they could be strict and fail it, if it passes emissions and the garage are not experts on that model you may get it through.
If the vehicle is built/registered etc post August 1992, then legally it MUST have a cat fitted. It doesnt state 2 ,3 ,4, 5 etc cats just that one must be fitted. So you're ok in that regard.
There will only be a very few small exceptions that that generalisation nevermind also those that revert to just a basic test.
What exactly is the vehicle that you think it might deviate from the above ? Is it unusual, modified ? other ?
There will only be a very few small exceptions that that generalisation nevermind also those that revert to just a basic test.
What exactly is the vehicle that you think it might deviate from the above ? Is it unusual, modified ? other ?
SMB said:
If you look under 7.1.3 reasons for rejection, a car can be rejected where a cat has been removed where it was originally fitted as standard. If the removal is obvious visually then they could be strict and fail it, if it passes emissions and the garage are not experts on that model you may get it through.
Yes, it's a reason only for point 3, which is as above. They can only reject, as I read it, if they have to check for it, but a modern vehicle should pass a BET so that check doesn't need to be done.If you look at the other reasons they all correspond to the check.
1. Check the exhaust is secure
1. Fail if it's wobbly
2. Check for holes
2. Fail for holes
3. Check for cat if fails a BET
3. Fail if cat is missing
-Dash- said:
Yes, it's a reason only for point 3, which is as above. They can only reject, as I read it, if they have to check for it, but a modern vehicle should pass a BET so that check doesn't need to be done.
If you look at the other reasons they all correspond to the check.
1. Check the exhaust is secure
1. Fail if it's wobbly
2. Check for holes
2. Fail for holes
3. Check for cat if fails a BET
3. Fail if cat is missing
It's a risk people take, visually a cat bypass or replacement pipe will be obvious and alert a tester. My interpretation of 7.1.3 is they can fail it if it's obvious one or more cats have been removed. The performance benefit is minimal by removal , during the longer warm up period for the cat to be effective enough to pass a bet the smell would alert the tester or a roadside inspection. As clean air zones appear wider you are just opening yourself up to being pulled over or refused an mot.If you look at the other reasons they all correspond to the check.
1. Check the exhaust is secure
1. Fail if it's wobbly
2. Check for holes
2. Fail for holes
3. Check for cat if fails a BET
3. Fail if cat is missing
The body that oversees tests is DVSA.
I'd suggest you raise this issue with them & see what they say.
https://www.gov.uk/getting-an-mot/problems-with-yo...
under the heading "If you’re unhappy with your MOT service"
I'd suggest you raise this issue with them & see what they say.
https://www.gov.uk/getting-an-mot/problems-with-yo...
under the heading "If you’re unhappy with your MOT service"
paintman said:
The body that oversees tests is DVSA.
I'd suggest you raise this issue with them & see what they say.
https://www.gov.uk/getting-an-mot/problems-with-yo...
under the heading "If you’re unhappy with your MOT service"
Not a bad shout, I've emailed DVSA posing the same question. Whether I get a reply or not is another thing!I'd suggest you raise this issue with them & see what they say.
https://www.gov.uk/getting-an-mot/problems-with-yo...
under the heading "If you’re unhappy with your MOT service"
-Dash- said:
E-bmw said:
Your garage isn't talking BS at all, you have removed cats, your car is post 1994 & therefore for you to remove the cats you have made your car illegal & therefore not able to pass an MOT based on the principle that you have removed/disabled part of the emission control system..
Such an authoritative statement, would you mind citing the regulation that mandates that? Given that as per my original post referencing the current MOT manual, I can't find anything (as part of the MOT and not C&U) that requires all cats to be present at all providing that the vehicle can pass a BET.stevieturbo said:
E-bmw said:
Your garage isn't talking BS at all, you have removed cats, your car is post 1994 & therefore for you to remove the cats you have made your car illegal & therefore not able to pass an MOT based on the principle that you have removed/disabled part of the emission control system.
However, as has been pointed out above not everyone sees it that black/white.
Except he does still have a cat fitted, and his car most probably will still pass the emissions test to prove it is fully functional as the test demands.However, as has been pointed out above not everyone sees it that black/white.
I never followed this up, so thought I would.
I wrote to VOSA and they wouldn't answer the question. The best they could give me was factory cats are required for type approval and not emissions.
I brought attention to it to a local MOT station who said that it is of course fine providing that it passes emissions, only then would it need to be checked. Otherwise there is no way anybody could have anything after-market (or even technically, replaced as a replacement wouldn't be the factory version).
As my emissions were not affected as I still had the primary cat in place, my MOT passed.
I wrote to VOSA and they wouldn't answer the question. The best they could give me was factory cats are required for type approval and not emissions.
I brought attention to it to a local MOT station who said that it is of course fine providing that it passes emissions, only then would it need to be checked. Otherwise there is no way anybody could have anything after-market (or even technically, replaced as a replacement wouldn't be the factory version).
As my emissions were not affected as I still had the primary cat in place, my MOT passed.
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