Emission Controls - Honda 1994 Accord Sedan Owner's Manual

Emission Controls

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
form photochemical "smog." Carbon
monoxide does not contribute to
smog creation, but it is a poisonous
gas.
Technical Information
The Clean Air Act
The United States Clean Air Act*
sets standards for automobile
emissions. It also requires that
automobile manufacturers explain to
owners how their emission controls
work and what to do to maintain
them. This section summarizes how
the emission controls work.
Scheduled maintenance is on page
133.
* In Canada, Honda vehicles comply
with the Canadian Motor Vehicle
Safety Standards (CMVSS) for
Emissions valid at the time they are
manufactured.
Crankcase Emission Control
System
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 from
the crankcase back to the intake
manifold. They are then drawn into
the engine and burned.
Evaporative Emission Control
System
As gasoline evaporates in the fuel
tank, an evaporative emission control
canister filled with charcoal adsorbs
the vapor. It is stored in this canister
while the engine is off. After the
engine is started and warmed up, the
vapor is drawn into the engine and
burned during driving.