
Engine management
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no inuence on the carbon dioxide (CO
2
) emissions, which are directly
proportional to the fuel consumption.
Direct injection of petrol is a good way of lowering fuel consumption. Because
a precise amount of fuel is injected directly into the cylinder, the consumption
can be controlled more accurately. However, only the area around the plug is
ignitable because the remainder of the cylinder is lled with air. With standard
direct injection systems, this reduces fuel consumption but results in higher
nitrogen oxide emissions. The resulting exhaust gases are not ideally suited
to a conventional three-way catalytic converter