Ford Focus - MOT emmissions

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Fri 22 Jul 2011 02:25
Ford Focus - MOT emmissions - Focus_Driver

I have a 2000 1.8 petrol focus which is due for MOT in a month. It passed easily last year but was quite close on the emmissions test. It was close on 2 tests, the others it was well within the limits.

The 2 results were:

CO fast idle: 0.20 % volume (limit = 0.20)

Natural idle:: CO: 0.28% volume (limit = 0.30)

As a comparison, the figures for the MOT the year before were 0.14 and 0.070. The year before that were even lower. Do these results have any significant meaning? The engine runs very well and doesn't smoke except in cold weather it appears to emit a lot of water vapour.

Do other factors affect the tests such as engine temperature, condition of the oil etc? But as you can see the values have been getting higher each year. Does this mean there could be a problem with the engine emmisions? If the car does not pass on the above 2 tests is it a small or big job to fix?

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Fri 22 Jul 2011 14:35
Ford Focus - MOT emmissions - unthrottled

I wouldn't worry. The engine will slowly cycle from slightly rich to slighly lean so, depending on where they 'catch it' with the exhaust sniffer, the CO levels will either be almost zero or quite near the limit. That's why a range of lambda from 0.97-1.03 is accepted.

What was your lambda value?

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Sat 23 Jul 2011 00:35
Ford Focus - MOT emmissions - Focus_Driver

Lambda was 1.004 so well within limit. If say the CO level was just over would they normally take a second reading?

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Sat 23 Jul 2011 02:23
Ford Focus - MOT emmissions - unthrottled

Yes.

From the motuk.co.uk manual;

Reasons for rejection:

b. In the 2nd fast idle test, one or more of the following exceeds the vehicle specific or default limits continuously for the last 5 seconds of the 30 second countdown"
. Carbon monoxide (CO)
. Hydrocarbons (HC)
. Lambda (l)

c. In the idle test. the following gas exceeds the vehicle specific or default limit continuously for the last 5 seconds of the 30 second countdown:
. Carbon monoxide (CO).

Not very stringent at all.

In spite of the moaning from some people with amateurishly modified engines, the MOT emissions test is a doddle for any properly adjusted engine to pass. If it doesn't, then something is clearly wrong and this should be addressed.

Every single UK spec spec diesel car and some UK spec petrol engines would fail a Californian spec. smog test.

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Sat 23 Jul 2011 08:38
Ford Focus - MOT emmissions - jc2

And so would most cars from the other 49 states!!!

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Sat 23 Jul 2011 12:55
Ford Focus - MOT emmissions - unthrottled

Not necessarily! 5 states have signed up to the Cali standards. Something that's not always considered when people ridicule US cars for being badly engineered because they don't make as much hp/cubic inch as euro equivalents.

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Sat 23 Jul 2011 15:47
Ford Focus - MOT emmissions - jamie745

The strict Californian emissions regulations are another reason why things like Hybrids are quite popular there, and wasnt California the first place to trial the Hydrogen Fuel Cell stuff?

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