Vauxhall Astra G Petrol 1.6 8v - High emissions at fast idle

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Fri 25 Jul 2014 23:32
Vauxhall Astra G Petrol 1.6 8v - High emissions at fast idle - autumnboy

My sons car MOT failure.

It failed it's Fast Idle Test:

CO level .0.85% Limit 0.30

HC level 97ppm Limit 200

Lambda 1.02 Limits 0.97 - 1.03

New complete exhaust system fitted some 3wks ago, from ex. manifold.

New plugs fitted 2mths ago

Engine management light never been lit/on.

Any clues/tips of causes of High emissions as above.

Would a Italian drive help this as he tends to be a careful driver to save fuel and low daily mileage max of 16 miles round trip twice a week of 50mph max.

Thanks

Edited by autumnboy on 25/07/2014 at 23:33

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Fri 25 Jul 2014 23:44
Vauxhall Astra G Petrol 1.6 8v - High emissions at fast idle - elekie&a/c doctor
From the figures shown,it would appear that your Xmas cracker catalyst is not doing much.these tend to only work properly if the engine gets to a very good hot temp.Is your engine running too cool.?
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Sat 26 Jul 2014 09:41
Vauxhall Astra G Petrol 1.6 8v - High emissions at fast idle - autumnboy

thanks,

Would the coolant sensor have any effect on this or should he check his operating temp re-Themostat.

thanks again

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Sat 26 Jul 2014 11:33
Vauxhall Astra G Petrol 1.6 8v - High emissions at fast idle - elekie&a/c doctor
Engine temp needs to be as hot as poss,Ideally over 95 degrees.How far does the temp gauge needle reach.?
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Sat 26 Jul 2014 18:07
Vauxhall Astra G Petrol 1.6 8v - High emissions at fast idle - autumnboy

He tells me,

The temp gauge runs in the lower part, unless in traffic then it rises midway.

Sounds like the Thermostat maybe lazy, letting it run on the cool side.??

thanks

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Sat 26 Jul 2014 18:28
Vauxhall Astra G Petrol 1.6 8v - High emissions at fast idle - elekie&a/c doctor
This could be the problem,needs sorting out.
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