The tires on your vehicle meet all
U.S. Federal Safety Requirements.
All tires are also graded for
treadwear, traction, and temperature
performance according to
Department of Transportation (DOT)
standards. The following explains
these gradings.
Uniform Tire Quality Grading
Quality grades can be found where
applicable on the tire sidewall
between tread shoulder and
maximum section width. Forexample:Treadwear 200
Traction AA
Temperature A
All passenger car tires must conform
to Federal Safety Requirements in
addition to these grades. Treadwear
The treadwear grade is a
comparative rating based on the wear
rate of the tire when tested under
controlled conditions on a specified
government test course. For
example, a tire graded 150 would
wear one and one-half (1 1/2) times
as well on the government course as
a tire graded 100. The relative
performance of tires depends upon
the actual conditions of their use,
however, and may depart
significantly from the norm due to
variations in driving habits, service
practices and differences in road
characteristics and climate.
Traction
The traction grades, from highest to
lowest, are AA, A, B, and C. Those
grades represent the tire's ability to
stop on wet pavement as measured
under controlled conditions on
specified government test surfaces of
asphalt and concrete. A tire marked
C may have poor traction
performance.
Warning: The traction grade
assigned to this tire is based on
straight-ahead braking traction tests,
and does not include acceleration,
cornering, hydroplaning, or peak
traction characteristics.
DOT Tire Quality Grading (U.S. Vehicles)
321
Technical Information
Table of Contents
The burning of gasoline in your
vehicle'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 formphotochemical‘‘smog. ’’Carbon
monoxide does not contribute to
smog creation, but it is a poisonousgas.
The Clean Air Act
The United States Clean Air Act
ꭧ
sets standards for automobile
emissions. It also requires that
automobile manufacturers explain to
owners how their emissions controls
work and what to do to maintain
them. This section summarizes how
the emissions controls work.
ꭧIn Canada, Honda vehicles comply
with the Canadian emission
requirements, as specified in an
agreement with Environment
Canada, at the time they are
manufactured.
Crankcase Emissions Control System
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 crankcase
ventilation valve routes them from
the crankcase back to the intake
manifold. They are then drawn into
the engine and burned. Evaporative Emissions ControlSystem
As gasoline evaporates in the fuel
tank, an evaporative emissions
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.
Onboard Refueling Vapor Recovery
The onboard refueling vapor
recovery (ORVR) system captures
the fuel vapors during refueling. The
vapors are adsorbed in a canister
filled with activated carbon. While
driving, the fuel vapors are drawn
into the engine and burned off.
Emissions Controls
326
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