Î
ÎThe United States Clean Air Act
sets standards f or automobile
emissions. It also requires that
automobile manufacturers explain to
owners how their emissions controls
workandwhattodotomaintain
them. This section summarizes how
the emissions controls work.
Scheduled maintenance is on page .
In Canada, Honda vehicles comply
with the Canadian Motor Vehicle
Saf ety Standards (CMVSS) f or
Emissions valid at the time they are
manuf actured.
The burning of gasoline in your car’s
engine produces several byproducts.
Some of these are carbon monoxide
(CO), oxides of nitrogen (NOx) and
hydrocarbons (HC). Gasoline
evaporating 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
f orm photochemical ‘‘smog.’’ Carbon
monoxide does not contribute to
smog creation, but it is a poisonous
gas.
Your car has a Positive Crankcase
Ventilation System. This keeps
gasses that build up in the engine’s
crankcase from going into the
atmosphere. The Positive Crankcase
Ventilation valve routes them fromthe crankcase back to the intake
manif old. They are then drawn into
the engine and burned.
As gasoline evaporates in the f uel
tank, an evaporative emissions
control canister f illed with charcoal
adsorbs the vapor. It is stored in this
canister while the engine is of f . Af ter
the engine is started and warmed up,
the vapor is drawn into the engine
and burned during driving.
The Onboard Ref ueling Vapor
Recovery (ORVR) system captures
the f uel vapors during ref ueling. The
vapors are adsorbed in a canister
f illed with activated carbon. While
driving, the f uel vapors are drawn
into the engine and burned of f .
156
The Clean Air Act
Crankcase Emissions Control
System Evaporative Emissions Control
System
Onboard Ref ueling Vapor
Recovery
Emissions Cont rols
T echnical Inf ormation248