2005 Ford Focus 1.6 Petrol - Ford Focus failed MOT on high CO emissions.

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Thu 31 Aug 2017 11:53
2005 Ford Focus 1.6 Petrol - Ford Focus failed MOT on high CO emissions. - veedoubleu

Hi all,

I bought this Ford Focus about a year ago and it's failed it's first MOT under my ownership.

The engine management light has been on for a few months (which I ignored, oops), and it said something about the catalytic converter, I can double check the full error later.


Anyway it's failed the MOT and here are the results...

Fast Idle Test
Engine Speed = 2565
CO = 0.36 (FAIL - MAX OF 0.20)
HC = 115
Lambda = 1.012

Second Fast Idle Test
Engine Speed = 2710
CO = 0.33 (FAIL - MAX OF 0.20)
HC = 111
Lambda = 1.011

Natural Idle Test
Engine Speed = 795
CO = 0.30 (PASS - JUST ON MAX LIMIT OF 0.30)

It's been suggested that I need a new catayltic converter fitted (it's a complicated twin one that takes hours to fit). So all in all this is a very expensive option, is there a possiblity it might not even fix the emissions problem?

Is there any common issues with this model of car that have a cheaper solution to the problem?

What about these Cat Cleaner additives I can put in the petrol tank?

By the way I don't have any issues with the performance of the car, it drives really well.

Thanks for any help here I appreciate it.

Cheers.

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Thu 31 Aug 2017 13:46
2005 Ford Focus 1.6 Petrol - Ford Focus failed MOT on high CO emissions. - RichardW

Find out why the EML is on, fix that, take it for a good thrash and see if it passes. However, with HC and lambda within spec, the cat not working properly is certainly a strong possibility.

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Fri 1 Sep 2017 10:30
2005 Ford Focus 1.6 Petrol - Ford Focus failed MOT on high CO emissions. - veedoubleu

Hiya cheers for replying, I've found out the error code...

P0420 - Catalyst System Efficiency Below Threshold.

I should also mention that there's no weird smoke coming out of my exhaust at all.

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Fri 1 Sep 2017 13:29
2005 Ford Focus 1.6 Petrol - Ford Focus failed MOT on high CO emissions. - Galaxy

As RichardW has said, take it for a nice long fast run, an "Italian Tune!"

Ask the MOT testing station whether they can carry out the emissions test as soon as you arrive at the beginning of the test, the car only has to pass the test once.

Edited by Galaxy on 01/09/2017 at 13:30

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Wed 27 Sep 2017 20:22
2005 Ford Focus 1.6 Petrol - Ford Focus failed MOT on high CO emissions. - veedoubleu

Hello everyone, just a quick update on this as I hate searching for threads myself and finding the original poster never writes how he got on : - D

Had to get a new catalytic converter in the end, this got the CO down to 0.02!

Cheers for the replies.

Edited by veedoubleu on 27/09/2017 at 20:22

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