CO2 Emissions

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Sat 7 Jun 2003 21:14
CO2 Emissions - Cardew
CO2 emissions - measured in g/km - are higher from an automatic car than the manual version of the same car/engine. I assume therefore that the emissions are measured under load conditions. The automatic having to work harder to maintain a set speed because of the losses in the auto box and different gearing.

Does anyone know the conditions under which they are measured?
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Sun 8 Jun 2003 08:38
CO2 Emissions - jc
The emission test consists of two parts:-
1. 0-15-0 kph,0-32-0 kph,0-50-0 kph.
These 3 sets of cycles are repeated 4 times from cold.
2. It is then followed by one much longer cycle which goes upto 120 kph.
As part of the legal test there is also a -8 deg C. cold test,an evaporative emission test,an idle test and a crankkcase emission test but none of these form part of the CO2 test.
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Sun 8 Jun 2003 09:46
CO2 Emissions - madman
To put it in laymans terms the more fuel you use the higher the CO2 will be. Auto nearly always use more fuel.
Bob T
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Mon 9 Jun 2003 13:17
CO2 Emissions - daveyjp
Owners of early smarts get stung by this difference on their road tax. Cars without the auto option pay the cheapest level, cars with the auto option (which never has to be used at it can still be manual) pay the higher band. Emission improvements across the range have removed this difference in the newer cars. From experience of driving in full auto the smart does need higher revs (3,500-4,000) to perform a smooth change in auto. In manual mode 2,500-3,000 is the norm. The car also holds in 4th at 30mph, when 5th can be used. Similarly at 40mph I can put the car in 6th and its doesn't labour, but the autobox doesn't consider 6th until about 60mph. All this adds up to higher emissions in auto mode.
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Mon 9 Jun 2003 16:22
CO2 Emissions - Cardew
Many new automatic cars are in a higher VED bracket(than the manual version) and under the new regulations cost more if it is a company car.

jc has answered the original query I had.
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