Peugeot 206CC - MOT emissions failure

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Tue 17 Feb 2015 14:38
Peugeot 206CC - MOT emissions failure - Crossbow

Just had an MOT failure on emissions for a high lambda reading of 9.998! Given that I understand the normal range is 0.97 to 1.03 this figure seems non-feasible. Last time it was 1.002. Any ideas anyone? is the testing station's equipment faulty?

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Tue 17 Feb 2015 23:09
Peugeot 206CC - MOT emissions failure - Andrew-T

An engine wouldn't run at a lambda of 10. This number represents the stoichiometric ratio of fuel to oxygen - if it's exactly 1, combustion should be completely clean. 10 fuel to 1 oxygen won't go (I think it's that way round).

I would guess it's a misread for 0.998, which is as close as makes no difference at all.

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Wed 18 Feb 2015 10:25
Peugeot 206CC - MOT emissions failure - Railroad.
I would certainly query it with the testing station. This figure cannot be correct because it's impossible. If your lambda figure is actually 0.998 then it's within spec and it should pass.
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Wed 18 Feb 2015 11:15
Peugeot 206CC - MOT emissions failure - jc2

Take it up with the Mot-that tester sounds as if he should not be testing.

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Wed 18 Feb 2015 11:40
Peugeot 206CC - MOT emissions failure - skidpan

I once had a car fail its MOT on emmisions. The garage said it was not adjustable and I needed to take the car into the main dealer. They tested it, said it was absolutely fine and gave me a read out as proof, no charge. Took read out to the original garage and they simply gave me an MOT cert.

A week later I was stopped at a portable road side emmision testing facility. Car passed with no issues even though I had only travelled about a mile from the office at the time.

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