As petrol evaporates in the fuel tank,
an evaporative emissions control
canister filled with charcoal absorbs
the vapour. It is stored in this
canister while the engine is off. After
the engine is started and warmed up,
the vapour is drawn into the engine
and burned during driving.
Your vehicle has a Positive
Crankcase Ventilation System. This
keeps gasses that build up in the
engine’s crankcase from going into
the atmosphere. The Positive Crank-
case Ventilation valve routes them
from the crankcase back to the
intake manifold. They are then
drawn into the engine and burned.
The burning of petrol in your vehicle’s
engine produces several byproducts.
Some of these are carbon monoxide
(CO), oxides of nitrogen (NOx) and
hydrocarbons (HC). Petrol evapo-
rating from the tank also produces
hydrocarbons. Controlling the
production of NOx, CO, and HC is
important to the environment. Under
certain conditions of sunlight and
climate, NOx and HC react to form
photochemical ‘‘smog.’’ Carbon
monoxide does not contribute to
smog creation, but it is a poisonous
gas.
Crankcase Emissions Control
System
Evaporative Emissions Control
System
Emissions Controls
Technical Information
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