Putting a decatted car through an MOT...

[Ads_172]

Just wondering if, for curiousity's sake if nothing else, anyone has put their decatted 1*2 through an MOT test to see the outcome?

Just how much would it fail the emissions test by?

 

[Laura]

YES... AND ALOT

well didnt put it through a mot just tested the emissions for a giggle

 

[Darmon]

yea, it'd fail the emissions so badly haha, you can also be fined for not having a cat from what I can remember - upto £5000 iirc

 

[phantomx0_1]

Not sure how much it would fail by. But it will fail unless you know someone who does MOT's ;-)

 

[adams182]

No quite a few people that will push a de-cat though the M.O.T having one fitted monday cant wait

 

[CHRIS172CUP]

mine's been wired up to the machine before, it's hilariously over the limit

 

[Eckascliovalver]

mine's been wired up to the machine before, it's hilariously over the limit

+1

You can smell it straight away too

 

[MRBILLYUK]

+1

You can smell it straight away too

I've had my Yozzasport exhaust and decat on for 6 days now . It really smells strong when you stand at the back of my car now , you can literally only stand there for a minute before you choke to death lol .

There's no way on earth it would pass an emissions test now .

 

[Fred@BTM]

bottle or whiskey normally fixes the problem if you get what i mean

 

[Ads_172]

Lol, sweet. Better speak to my friendly MOT tester before getting it done to make sure I can drop the car off at his come MOT time collect it a few hours later, certificate in hand!

 

[TooneySonic]

only 45mins to change but yeah i did the same, ran it through the emissions for fun = epic fail

 

[GazM]

put mine thru, failed miserably!

 

[chrispy.clio]

I took my 182 to see how badly it would fail
The guy said it should be 0.2 but mine was 8.7 lol
I cant remember what the 0.2 was measured in, but the stuff coming out of the exhaust was killing the birds and the bees
lol

 

[st3ve]

lol @ those figures, does a decat make it run richer at all?

 

[Da]

Probably yeah as the sensors think the cat is foobared!

 

[jablitt]

lol, i'm really not looking forward to changing my decat for the original converter to pass its MOT. its a right s**t job on the 172! does anyone know a friendly MOT tester in the Leicestershire/loughborough area.

 

[franx]

sensors do'nt do anything to it.. the second one just tells you if your cat is in proper working order

only the first sensor (before cat) , when broken, will get the engine in a sort of safe running mode and probably richen up the mixture to prevent lean running damage

 

[MarkCup]

Mine's been MOT tested a couple of times with the decat on, both times it was almost a pass, 2 of the levels were ok, the 3rd was only just slightly over.

Why is that if everyone else's fails badly?

 

[franx]

first one does read and adjust mixture in some way but not cat related.

Mark mine was also just above allowed once , and with a sporcat, heated up well, it was spot on once.

I think the car gets the best readings when the engine is really hot

I'm guessing the 8,7 of one of the above was on a cold car..

 

[iimushroomzii]

Its not what you know, its who you know. Friendly mot testers FTW.

 

[Andyman]

Would the reading not be effected by how the cars buring its fuel, the fueling set up?

EG: if the car is running a bit lean the reading will be closer to a catted car, a bit rich and its going to be more off the mark?

 

[franx]

^ i would think so yes

Mark's car must be running a bit lean. Could be the reason why it is so bloody quick

 

[Andyman]

^ i would think so yes

Mark's car must be running a bit lean. Could be the reason why it is so bloody quick

Dont you mean rich?

 

[MarkCup]

Is that good or bad?

Would/could it be because for 99.9% of its 107,000 mile life so far it's only ever been fed Shell Optimax/V-Power?

 

[franx]

Dont you mean rich?



no i meant lean.. I remember the man who tuned my Subaru said something about a car one the verge of running lean runs fastest . Trick is to be carefull with this (i think more for turbo powered cars) as it could cause serious damage when running too lean

 

[franx]

Is that good or bad?

Would/could it be because for 99.9% of its 107,000 mile life so far it's only ever been fed Shell Optimax/V-Power?

i think yours runs optimal as it's been going forever i've read , your choice of fuel could well have something to do with it. Optimal combustion going on in there

 

[st3ve]

Is that good or bad?

Would/could it be because for 99.9% of its 107,000 mile life so far it's only ever been fed Shell Optimax/V-Power?

Putting V-Power into a standard 172/182 will have virtually no improvement in performance.

 

[geesus69]

Putting V-Power into a standard 172/182 will have virtually no improvement in performance.

who said anything about performance? the thread is about emissions

and when you say 'virtually' no improvement is that a way of saying it might, but you don't know for sure?

 

[mattjk]

I think if running lean nox increases and if running rich then hydrocarbons increase. Could be wrong though havnt read up on this stuff for a while!