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Temperature
The temperature grades are A (the
highest), B, and C, representing the
tire's resistance to the generation of
heat and its ability to dissipate heat
when tested under controlled
conditions on a specified indoor
laboratory test wheel. Sustained high
temperature can cause the material
of the tire to degenerate and reduce
tire life, and excessive temperature
can lead to sudden tire failure. The
grade C corresponds to a level of
performance which all passenger car
tires must meet under the Federal
Motor Vehicle Safety Standard No.
109. Grades B and A represent
higher levels of performance on the
laboratory test wheel than the
minimum required by law.Warning: The temperature grade for
this tire is established for a tire that
is properly inflated and not
overloaded. Excessive speed,
underinflation, or excessive loading,
either separately or in combination,
can cause heat buildup and possible
tire failure.
DOT Tire Quality Grading (U.S. Vehicles)
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The tires that came on your vehicle
have a number of markings. Those
you should be aware of are described
below.
Tire SizeWhenever tires are replaced, they
should be replaced with tires of the
same size. Below is an example of
tire size with an explanation of what
each component means.P235/55R18 99V
P -Vehicle type (P indicates
passenger vehicle).
235 -Tire width in millimeters.
55 -Aspect ratio (the tire's
section height as a
percentage of its width).
R -Tire construction code (R
indicates radial).
18 -Rim diameter in inches.
99 -Load index (a numerical
code associated with the
maximum load the tire can
carry).
V -Speed symbol (an
alphabetical code indicating
the maximum speed rating).
Tire Identification Number (TIN)The tire identification number (TIN)
is a group of numbers and letters that
look like the following example. TIN
is located on the sidewall of the tire.
DOT B97R FW6X 2202
DOT -This indicates that the tire
meets all requirements of
the U.S. Department of
Transportation.
B97R -Manufacturer's
identification mark.
FW6X -Tire type code.
TIRE LABELING EXAMPLE
(1)
(1)
(2)
(3)
(4)
(1) Tire Size
(2) Tire Identification Number (TIN)
(3) Maximum Tire Pressure
(4) Maximum Tire Load
2202 -
year
week Date of manufacture.
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Glossary of Tire Terminology
Cold Tire Pressure-The tire air
pressure when the vehicle has been
parked for at least three hours or
driven less than 1 mile (1.6 km).
Load Rating -Means the maximum
load that a tire is rated to carry for a
given inflation pressure.
Maximum Inflation Pressure -The
maximum tire air pressure that the
tire can hold.
Maximum Load Rating -Means the
load rating for a tire at the maximum
permissible inflation pressure for that
tire.
Recommended Inflation Pressure -
The cold tire inflation pressure
recommended by the manufacturer.
Treadwear Indicators (TWI) -
Means the projections within the
principal grooves designed to give a
visual indication of the degrees of
wear of the tread. Tire Pressure Monitoring System
(TPMS)
-Required Federal
Explanation
Each tire, including the spare (if
provided), should be checked
monthly when cold and inflated to
the inflation pressure recommended
by the vehicle manufacturer on the
vehicle placard or tire inflation
pressure label.
(If your vehicle has tires of a different
size than the size indicated on the
vehicle placard or tire inflation
pressure label, you should determine
the proper tire inflation pressure for
those tires.) As an added safety feature, your
vehicle has been equipped with a tire
pressure monitoring system (TPMS)
that illuminates a low tire pressure
telltale
when one or more of your tires is
significantly under-inflated
Accordingly, when the low tire
pressure telltale illuminates, you
should stop and check your tires as
soon as possible, and inflate them to
the proper pressure.
CONTINUED
Tire Labeling, Tire Pressure Monitoring System (TPMS)
-Required Federal Explanation
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Driving on a significantly under-
inflated tire causes the tire to
overheat and can lead to tire failure.
Underinflation also reduces fuel
efficiency and tire tread life, and may
affect the vehicle's handling and
stopping ability.
Please note that the TPMS is not a
substitute for proper tire
maintenance, and it is the driver's
responsibility to maintain correct tire
pressure, even if under-inflation has
not reached the level to trigger
illumination of the TPMS low tire
pressure telltale.Your vehicle has also been equipped
with a TPMS malfunction indicator to
indicate when the system is not
operating properly. The TPMS
malfunction indicator is combined
with the low tire pressure telltale.
When the system detects a
malfunction, the telltale will flash for
approximately one minute and then
remain continuously illuminated.
This sequence will continue upon
subsequent vehicle start-ups as long
as the malfunction exists.
When the malfunction indicator is
illuminated, the system may not be
able to detect or signal low tire
pressure as intended.TPMS malfunctions may occur for a
variety of reasons, including the
installation of replacement or
alternate tires or wheels on the
vehicle that prevent the TPMS from
functioning properly.
Always check the TPMS malfunction
telltale after replacing one or more
tires or wheels on your vehicle to
ensure that the replacement or
alternate tires and wheels allow the
TPMS to continue to function
properly.Tire Pressure Monitoring System (TPMS)
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The burning of gasoline in your
vehicle's engine produces several by-
products. 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. 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 emissions controls
work and what to do to maintain
them. This section summarizes how
the emissions controls work.
Scheduled maintenance is on page
418.ᤳIn Canada, Acura 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 Control
System
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.
Emissions Controls
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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.
Exhaust Emissions Controls
The exhaust emissions controls
include three systems: PGM-FI,
ignition timing control, and three
way catalytic converter. These three
systems work together to control the
engine's combustion and minimize
the amount of HC, CO, and NOx that
come out the tailpipe. The exhaust
emissions control systems are
separate from the crankcase and
evaporative emissions control
systems.
PGM-FI SystemThe PGM-FI system uses sequential
multiport fuel injection.
It has three subsystems: air intake,
engine control, and fuel control. The
powertrain control module (PCM)
uses various sensors to determine
how much air is going into the
engine. It then controls how much
fuel to inject under all operating
conditions.Ignition Timing Control SystemThis system constantly adjusts the
ignition timing, reducing the amount
of HC, CO, and NOx produced.Three Way Catalytic ConverterThe three way catalytic converter is
in the exhaust system. Through
chemical reactions, it converts HC,
CO, and NOx in the engine's exhaust
to carbon dioxide (CO
2), nitrogen
(N
2), and water vapor. Replacement Parts
The emissions control systems are
designed and certified to work
together in reducing emissions to
levels that comply with the Clean Air
Act. To make sure the emissions
remain low, you should use only new
Acura replacement parts or their
equivalent for repairs. Using lower
quality parts may increase the
emissions from your vehicle.
The emissions control systems are
covered by warranties separate from
the rest of your vehicle. Read your
warranty manual for more
information.
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The three way catalytic converters
contain precious metals that serve as
catalysts, promoting chemical
reactions to convert the exhaust
gasses without affecting the metals.
The catalytic converters are referred
to as three-way catalysts, since they
act on HC, CO, and NOx.
Replacement units must be original
Acura parts or their equivalent.
The three way catalytic converter
must operate at a high temperature
for the chemical reactions to take
place. It can set on fire any
combustible materials that come
near it. Park your vehicle away from
high grass, dry leaves, or other
flammables.
A defective three way catalytic
converter contributes to air pollution,
and can impair your engine's
performance. Follow these
guidelines to protect your vehicle's
three way catalytic converter.●Always use unleaded gasoline.
Even a small amount of leaded
gasoline can contaminate the
catalyst metals, making the three
way catalytic converter ineffective.
●Keep the engine well maintained.●Have your vehicle diagnosed and
repaired if it is misfiring,
backfiring, stalling, or otherwise
not running properly.
THREE WAY CATALYTIC CONVERTERS
Three Way Catalytic Converter
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Testing of Readiness Codes
If you take your vehicle for an
emissions test shortly after the
battery has been disconnected or
gone dead, it may not pass the test.
This is because of certain‘‘readiness
codes ’’that must be set in the on-
board diagnostics for the emissions
systems. These codes are erased
when the battery is disconnected,
and set again only after several days
of driving under a variety of
conditions. If the testing facility determines that
the readiness codes are not set, you
will be requested to return at a later
date to complete the test. If you must
get the vehicle retested within the
next two or three days, you can
condition the vehicle for retesting by
doing the following.
1. Make sure the gas tank is nearly,
but not completely, full (around
3/4).
2. Make sure the vehicle has been parked with the engine off for 6
hours or more.
3. Make sure the ambient temperature is between 40° and
95°F (4° and 35°C). 4. Without touching the accelerator
pedal, start the engine, and let it
idle for 20 seconds.
5. Keep the vehicle in Park. Increase the engine speed to 2,000 rpm, and
hold it there until the temperature
gauge rises to at least 1/4 of the
scale (about 3 minutes).
6. Without touching the accelerator pedal, let the engine idle for 20
seconds.
7. Drive your vehicle for 30 seconds while accelerating.Emissions Testing49011/06/16 17:42:51 12 ACURA RDX MMC North America Owner's M 50 31STK650 enu