MOT emissions testing - CAT/no CAT

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skinthespin
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MOT emissions testing - CAT/no CAT

Post by skinthespin »

This is a reply from VOA regarding impoted cars and MOT emissions testing. sticky pease admins!!

“The lack of a catalytic converter is not an automatic fail in itself, but a vehicle may struggle to meet the required emission limits without one. Prior to 31 July 1992, a spark ignition engine is required to meet limits of CO<=3.5% and HC<=1200ppm. Between 1 August 1992 and 31July 1995, the limits will depend on whether or not the vehicle is listed in the current edition of the In Service Exhaust Emission Standards for Road Vehicles book ( currently the Ninth Edition) which all MOT stations are required to hold. If there is an exact match in this book for the vehicle ( regarding engine number/type, model, chassis no, etc. The exact requirements vary between manufacturers) then the vehicle will be tested to the limits in the book. If an exact match cannot be found, the vehicle will again need to meet limits of CO<=3.5% and HC<=1200ppm. I have looked up your particular model and engine and, as stated in your e-mail, this combination is not listed and therefore the vehicle would need to meet limits of CO<=3.5% and HC<=1200ppm. From 1 August 1995, the requirements again depend on whether or not the vehicle is listed in the Emissions book. As your particular combination is not listed, vehicles of this age would need to be tested to the following limits: Minimum oil temperature : 60C Idle (450 - 1500rpm) CO<=4.5% Fast Idle (2500-3000rpm) CO<=0.3% HC<=200ppm Lambda= 0.97 to 1.03 There is one possible exemption to the above requirements. If the customer can provide a letter from the manufacturer, quoting the chassis number and engine number of the vehicle, stating that the engine as originally installed could not meet the relevant UK emissions limits. In this case, the vehicle can be tested to the next lowest limit.” Hope this clears things up...

Emissions testing covers both Diesel and petrol engines.
There are some general considerations:
One important issue must be cleared up straight away. There is no requirement for a catalytic converter to be fitted to any vehicle, regardless of its age. It is however the most popular way of ensuring engines meet the emission legislation. The MOT test is testing the emissions from the tailpipe and if those emissions meet the standard then the vehicle passes. The term 'cat' test is inappropriate, the correct term is 'advanced emission test'. Its not the 'cat' that's being tested. There are a number of vehicles which are subject to the 'advanced emission test' but are capable of meeting the requirements without the use of a catalytic converter.
Kit cars and amateur built vehicles are regarded as pre 1st August 1975 vehicles for the purposes of MOT emissions testing and are subject to a visual check only. The age of the engine is not taken into account. SVA(single vehicle approval) introduces some problems and these are complex, the SVA manual is the source of information. In a nutshell all vehicles get a "visual check" and vehicles first used after 1/8/75 or with an engine manufactured after this date get a metered check or a CAT test if they are listed in the emissions handbook or are on the emissions tester database. After August 1995 they get a CAT test. Amateur built vehicle SVA emissions tests are based on the vehicle build date unless there is proof that the engine is earlier. If a date cannot be determined, until 31 March 2001 they will get a non CAT test. From the 1st April 2001 the effective date will be assumed to be 1st August 1997, i.e they will get a CAT test unless there is proof of the date of manufacture of the engine. Also, dual fuel (petrol/gas) are tested in both modes.
Personal imports are tested according to date of first use. To claim exemption, a letter from the vehicle manufacturer must be produced at the time of test.
Modified engines must still meet the requirements.
An older engine fitted to a vehicle will be tested to the age of the engine (evidence needed). A newer engine fitted to an older car will be tested to the age of the car i.e whichever is the oldest.
Vehicles which are not passenger cars are tested to different emissions limits in most cases. A passenger car is constructed to carry passengers, has no more than 5 seats excluding the driver, does not exceed 2500kg gross weight and is not a goods vehicle i.e pick-up, van or truck.
It will be necessary for evidence of first used dates to be produced in some cases (personal number plates, 1987's for seat belts and 1992's/94's for emissions) i.e V5 reg document or VE103 for leased/hired vehicles. Some vehicles may have been stored for long periods before being distributed by manufacturers. In these cases, if the vehicle was manufactured at least 6 months before its date of first use then the date of manufacture is used for test requirements.
Engines must be thoroughly warmed up and the oil temperature tested prior to testing (80 degrees C for most "CAT" tests although some are as low as 40 and 80 degrees C for Diesels). It's permissable for the emissions test to be carried out as soon as the vehicle arrives (environmentally friendly too) as long as the rest of the test is carried out on the same day by the same tester.
Any obstructions at the tailpipe which prevent the test probe being inserted will result in failure.
From 1st August 2001 a simplified emissions check was introduced and this will be carried out on vehicles prior to doing a full "CAT" test. If the vehicle meets the requirements during this BETs (basic emission test) then it passes. There will be no need to measure the engine temperature using the analyser probe but the vehicle must be at normal running temperature. However, engine rpm will still be measured. If the vehicle fails the BET then the full "CAT" test is applied.
The BET standards are:
Fast idle 2500-3000rpm
CO no more than 0.3%
HC no more than 200 parts per million
Lambda between 0.97 and 1.03
Normal idle 450-1500rpm
CO no more than 0.5%
MartG
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Re: MOT emissions testing - CAT/no CAT

Post by MartG »

fyi - my decatted '91 G-Ltd produced the following figures last Saturday:

CO level 1.05% ( limit is max. 3.5 )
HC level 162ppm ( limit is max 1200 )
Speedy
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Re: MOT emissions testing - CAT/no CAT

Post by Speedy »

Please note - the information above is provided without any guarantees, and is for your general benifit.

Vosa (the people responsible for MOT testing procedures) can be found here :
http://www.vosa.gov.uk/vosa/mottestersg ... idance.htm

If you have a problem with the way your car has been tested, please get in touch with VOSA, not IMOC!
unyonion
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Re: MOT emissions testing - CAT/no CAT

Post by unyonion »

I had a look at a few posts on here and on mr2oc and here is my post about the humungous hassle just to get my 2 MOT'd

http://www.mr2oc.co.uk/index.php?name=F ... 082#426082

hope it helps anyone else unfortunate to have this issue

Mark
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Re: MOT emissions testing - CAT/no CAT

Post by Quigonjay »

MartG wrote:fyi - my decatted '91 G-Ltd produced the following figures last Saturday:

CO level 1.05% ( limit is max. 3.5 )
HC level 162ppm ( limit is max 1200 )


was curious about mine after reading that so dug out mine from last mot
rev3 tubby, mongoose exhaust, de cat pipe -

CO level 0.76%
HC level 129 ppm
:shock:

it would have to be a particularly poorly engine to fail the emisions test
BrianUK
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:)

Post by BrianUK »

It helps to make sure you have a high quality fuel in the tank prior to the MOT as well - So forget AZDA specials for a week or so prior to the test!

:) Brian
zebidi
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Re: MOT emissions testing - CAT/no CAT

Post by zebidi »

V-Power all the way! Never anything else people =; :thumleft:
buish
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Re: MOT emissions testing - CAT/no CAT

Post by buish »

turbo cars have cleaner emissions.
SteveW
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Re: MOT emissions testing - CAT/no CAT

Post by SteveW »

V Power all the way too.

Also for other information the limits are mega easy to pass of 3.5% co.

My decatted 92 GT4 with a constantly running cold start injector (i didn't know fixed it now) gave 0.9%co after fixing the cold start injector went down to 0.35% CO.

Ten times less than required!
nathan smith

Re: MOT emissions testing - CAT/no CAT

Post by nathan smith »

mot garages now use the 13th edition ehaust standards book. if vehicle being tested is not in the book,then tester must use default limits,these are basicaly not cat limits (pre 92)eg.mr2 turbos are not in this book
Nickstapleton
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Re: MOT emissions testing - CAT/no CAT

Post by Nickstapleton »

Hi all just been reading some of the above info and have a Q, my 92 UK Mk2 N/A has just failed its emmisions test, reading something like 7.0 Co2, now from what I can understand this amount is well out of tolerence, however I'm not convinced the garage I took it too knows much about MR's. I need some help here as my car does not have a cat fitted as standardand and no lambder sensor on exhaust, however have just recently fitted a new front flexi section (my other broke) plus I have got an induction type air filter with the other sensor fitted for the intake, would this make any difference and how do I resolve this emmisions matter.
Mechanic has said that he may be able to adjust something to bring emmisions down, dont know what tho.
By the way this car has been completely standard since it was first registered, has been serviced by Toyota since it was bought, all the stamps in log book, has however got around 150000 on clock, plus I recently put a new rad on her cos the other had a blow out.
Does anyone have any ideas please, hate being without my car.
peterc
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Re: MOT emissions testing - CAT/no CAT

Post by peterc »

mine just sailed through 3rd mot this time with downpipe and berk exhaust fitted .seems that they were reving the car endlessly, and poking something up the exhaust .
after the owner said they were having a few probs with emmissions my car, but it was no prob. he said he had noticed the exhaust .
i mentioned that being before aug 95 it was ok to remove the cat ,to which he replied that the date was something else and that he would overlook whatever was showing on his equipt.
by the way my engine has great compression and pulls hard with no noises /smoke at all .
the garage is a small concern that looks after 4 vehicles of mine a family run business that is always very busy, the policy is it seems to make you aware of anything that may need attention.i really feel 100% confident in his work although the prices are very reasonable,
just checked results and the mot shows figs co-0.01,hc-14,lamb-1.008 nat test co-0.001
Shmed
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Re: MOT emissions testing - CAT/no CAT

Post by Shmed »

My rev 2 tubby failed on emissions (4%), and then only passed with some 'fuel cleaner' which got me down to 3.5%.

Does that mean I'm running rich and how can I lower my emissions? I am getting about 200KM from a full tank.
Martin F
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Re: MOT emissions testing - CAT/no CAT

Post by Martin F »

Shmed wrote:My rev 2 tubby failed on emissions (4%), and then only passed with some 'fuel cleaner' which got me down to 3.5%.

Does that mean I'm running rich and how can I lower my emissions? I am getting about 200KM from a full tank.



lol, thats not good, i only got 180 km to a full tank last week and that peed me off so i know how you feel...

what ecu is your car using ?
Shmed
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Re: MOT emissions testing - CAT/no CAT

Post by Shmed »

Standard Rev 2 I think. I checked out most of my sensors when I was rebuilding the car too, so not sure about that. I seem to remember the O2 readings were out when I checked the ECU pins, but I don't have any error codes.

:-k
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toxo
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Re: MOT emissions testing - CAT/no CAT

Post by toxo »

Found this URL recently, emissions data issued by the DFT:

http://www.dft.gov.uk/vosa/inserviceexh ... hicles.htm
IMOC-UK - the only club to win 'Best Club Stand' at JAE more than once, and twice in a row!
4ndee
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Re: MOT emissions testing - CAT/no CAT

Post by 4ndee »

1990 n/a 3s-ge

tested today, de-cat pipe too. :D

0.570: CO% vol
169: HC ppm
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toxo
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Re: MOT emissions testing - CAT/no CAT

Post by toxo »

Just had mine done again.

Rev3 turbo, fresh head rebuild. Always run on Tesco 99.

CO: 0.36%
HC: 64ppm
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GBTurbo
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Re: MOT emissions testing - CAT/no CAT

Post by GBTurbo »

I had mine done last year ive got a rev 3 turbo with a decat fitted and it failed. I had to swap it for the original cat.

Cant be bothered to dig out the readings but I was abit dissapointed because I thought it would go through on the decat waaaaaaaaaaaah :mad:

But I can change it over in about and hour and a half now
swaggansway

Re: MOT emissions testing - CAT/no CAT

Post by swaggansway »

just tell them it is not the origanal engine from the car....say it is from a early j reg and you have a imidate pass!

always worked for me but I was being honest, they never asked for proof!

besides old cats don't do much in means of filtering.... there are additives out there that will het you through too failing that just bolt ya cat back on it only takes half an hour :thumleft:
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