Sleeved Lambda at MOT time?

9th April 2011, 21:20

Does the 2nd Lambda on a MK2 VTS have to be in the exhaust to pass the MOT?

I've got a MK1 Cat ready to fit, but that will leave the second Lambda (which checks the CAT is working properly) with nowhere to plug in.

It should read clean air fine if it's sleeved and cable tied out of the way, but is that a fail on the MOT, since technically it's not reading the exhaust gases to check the CAT is functioning.

9th April 2011, 21:24

Your emissions will be out...therefor you will fail.

Having a lambda or not, doesnt come into it. Its what is comming out the end of the tail pipe, that matters.

9th April 2011, 21:24

Doubt it.

As long as the car passes its emissions test then will be ok

9th April 2011, 21:35

Which i doubt it will, as the lambda reading will be all over the shop.

9th April 2011, 21:41

The Lambda should just be reading clean air though surely, so as if the Cat is doing it's job?

9th April 2011, 21:51

But it wouldn't be doing its job..

the Post cat lambda would be reading clean air.. Where as in actual fact, the air in the exhaust may be crap, and the fueling and all sorts would be getting messed about because of it.

9th April 2011, 21:52

Quote:

Originally Posted by -Dan-

The Lambda should just be reading clean air though surely, so as if the Cat is doing it's job?

Emissions go past lambda one
Through cat
Past lambda two. Which reads the emissions and says, oi lambda one, give me more or less Emission.

Lambda one then say oh ok, oi, ecu, change the mixture.

This happens constantly, but the sencond lambda is now saying, yeah man, thats amazing, you could eat your dinner off this shit.

So when thefoot is on the throttle, dumping fuel, brininging in warm air, it doesnt think, oh wait no. Too much, adjust it mr ecu please. It just accepts it.

Aslong as the cat, it working fine, you should be alright! And hasnt been abused.
But dont be suprised if you fail, because your killing the cat with toomuch fuel. As it cloggs the cat up, and it become defective.

Lambdaz play such a big role.

9th April 2011, 22:48

Good stuff mate thanks muchly.

10th April 2011, 10:10

mine passed with a sleeved lambda.

10th April 2011, 10:21

Quote:

Originally Posted by tonto_VTR

Emissions go past lambda one
Through cat
Past lambda two. Which reads the emissions and says, oi lambda one, give me more or less Emission.

Lambda one then say oh ok, oi, ecu, change the mixture.

This happens constantly, but the sencond lambda is now saying, yeah man, thats amazing, you could eat your dinner off this shit.

So when thefoot is on the throttle, dumping fuel, brininging in warm air, it doesnt think, oh wait no. Too much, adjust it mr ecu please. It just accepts it.

Aslong as the cat, it working fine, you should be alright! And hasnt been abused.
But dont be suprised if you fail, because your killing the cat with toomuch fuel. As it cloggs the cat up, and it become defective.

Lambdaz play such a big role.

best way i have ever seen car emissions described.... im fucked ive got a 16v in a 1.1 and no cat...... plus i think by the time i got my mot the throttlebodies will be on. that should be interesting

10th April 2011, 11:09

I was under the impression that the pre-cat lambda did all the air/fuel ratio work whereas the post-cat lambda was used by the ecu to see if there is any changes in o2 content and thus if the cat is working or not.

10th April 2011, 16:57

Quote:

Originally Posted by s34n

best way i have ever seen car emissions described.... im fucked ive got a 16v in a 1.1 and no cat...... plus i think by the time i got my mot the throttlebodies will be on. that should be interesting

I see youre from plymouth.
When the mot is due, let me know. Ill sort it out