Unsure about emmisions? please read

[alban1973]

Hi folks..  A fellow member asked about emissions for the MOT test, I take around 15 to 20 cars for MOT\'s each month, the most asked and feared part of the MOT test for people seems to be the emission test, I actually think this is the least worring and very rarely come across a problem.  Now I have been back and forth today and actually remembered to ask the actual legality on year models etc for cat\'s and figures. My friendly MOTer came up with the following. VOSA vehicle emssion test model guide volume 11, or something to that effect, this gives the exact figures for certain cars which the computer system also knows, so cutting to the case..  For all you FD owners out there who are concerned about your emissions, here is the situation.  Any car after 95. some m\'s and from n reg have to by law have a cat fitted and the limit is 0.5% I did not take down the lambda or the hc figures, Now the but...  in the ubove mentioned book, if the chassis number of the vechicle has figures of  "FD13B2" and also before the 95 date then the co% content is also 0.5%  this is a cat vehicle and you can not get out of that figure, if your chassis number is any different to that then the standard 3.5% is the standard figure and the cat will not be important, unless it is a 95 on car. I can hear a rumble of foot steps of people running to check their chassis numbers.... I hope that clears up the minefield of unsureness.  or have I just really confused the issue??

[vxer]

Is this for UK cars, or imports too?

Ta, Paul.

[DarranJones]

Man that sux, I hate this government.

Does this mean that when the cat on my 95(N) rex crumbles to dust I have to replace it rather than change to a straight through?  :confused:

If it does I might trade mine in for an older car.

[alban1973]

Is this for UK cars, or imports too?

Ta, Paul.

I would assume yes if it has that chassis number, if not the it will be down to age.. I will enquire, but fairly certain,  Just remeber this is the written down version, and what the computer will pick up on, there ofcourse will be ways around it, but it is finding them :Hammer

[DC-TYPER]

thats good. i have a 93 L reg. and my mot guy said that the emissions were low enough to take the cat off:3gears-lh

[Prof]

I have no CAT on and FC 13BT - and my CO is 0.44%, with HC\'s at 244 ppm.

These are well under the 3.5% and 1200ppm limits, but I suspect it would even pass the more stingent later tests.  Trick is to get your engine tuned tip top - then it wont be chucking out filth  :p

[alban1973]

I have no CAT on and FC 13BT - and my CO is 0.44%, with HC\'s at 244 ppm.

These are well under the 3.5% and 1200ppm limits, but I suspect it would even pass the more stingent later tests.  Trick is to get your engine tuned tip top - then it wont be chucking out filth  :p

I agree, the upper limit of 3.5% co, is way too high for most vehicles anyway, most modernish cars without cats are around 1 to 1.5% manuf figures. I am not sure what ported and highly modified rotaries are running at, or if it is a problem to get them turned down for the test. I do know that a standard uncatted rotary with the airpump still fitted are pretty clean, Just like yours is proff..

[Ricco_04]

Crikey, I didn\'t think they would be that low.  I have been reading this thread with interest cause I wanted to know what emissions volume people where getting with no cat, guess this answers it.

Although this would put me in the 0.5% bracket if i\'m remembering the start of my chassis number correct (which I cant have done cause I get the 3.5% on my last test

Woo hoo, come on full decat! :D:D:D:D:D:D:D  :cheers

[iaint]

Last MOT (next one is looming!!!) the only thing the tester measured was CO2 levels - the initial reading was 18 against a pass mark of 3 (no clue if that\'s a % or what!).  I then remembered that the ECU \'had reset itself\' informed the tester, made corrected the ECU\'s mode and passed no worries.

Much will depend on the flexibility of the tester and how much they like your car!

The figures in \'the book\' where a chassis number is quoted is for vehicles as originally sold in the UK.  As most of us FD owners drive imports a different set of standards apply.  Also, as mine is an early 92 car it is inline for the non-cat test anyway.  

The removal of any cats will not make a car like mine fail the test BUT the removal of the airpump will (which is my car\'s problem).

[nikp]

I\'ve taken mine to the same garage 2 years running, and it was NEVER tested for emsisions. the reason? J regsitered car, so they therefore took it as 1991, whereby the emissions do not have to be tested.

[DC-TYPER]

OK, mine an L 93. do the cats have lambda sensors on them?
if i take my cat off. what will this do performance wise?
will my car run sluggish or better?
:wiggle

[nikp]

Lambda sensor is in the downpipe before the cat. You\'d need a straigt through pipe to replace the cat. Depending upon you\'re other mods though, you may need a mappable ECU and a remap if you\'re removing the cat.

[alban1973]

I\'ve taken mine to the same garage 2 years running, and it was NEVER tested for emsisions. the reason? J regsitered car, so they therefore took it as 1991, whereby the emissions do not have to be tested.

older cars do need to be tested and conform to the 3.5% co limit, but, testers do not always test them as they do not need to prove that they have passed by keeping a print out of the actual test. it is down to the individual tester and what they think. I\'m sure if it went in running poor and obviously had a problem they would test it.

[DC-TYPER]

Lambda sensor is in the downpipe before the cat. You\'d need a straigt through pipe to replace the cat. Depending upon you\'re other mods though, you may need a mappable ECU and a remap if you\'re removing the cat.

NO MODS, MIGHT BE GETTING AN INTERCOOLER THOUGH(EVENTUALLY)

[MikeLMR]

older cars do need to be tested .

it depends how old, there is a statement about pre 86 (I think its 86 I\'d need to check) rotaries that exempts them from Emmisions testing bar the visual smoke test

I\'ve no idea what the computers say now though ... although I do believe they cannot make any retrospective changes so it should still apply!