2003 SUBARU IMPREZA WRX four wheel drive

Starting and operating
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and states using two-wheel dynamometers in their
emission testing programs have EXEMPTED
Subaru AWD vehicles from the portion of the testing
program that involves a two-wheel dynamometer.
There are some states that use four-wheel
dynamometers in their testing programs. When
properly used, that equipment will not damage an
AWD Subaru vehicle.
Under no circumstances should the rear wheels be
jacked off the ground, nor should the driveshaft be
disconnected for state emission testing.
WARNING
Testing of an All-Wheel Drive vehicle must
NEVER be performed on a single two-wheel
dynamometer. Attempting to do so will result in uncontrolled vehicle movement and may
cause an accident or injuries to persons
nearby.
CAUTION
Resultant vehicle damage due to improper testing is not covered under the SUBARU Lim-
ited Warranty and is the responsibility of the state inspection program or its contractors orlicensees.
The EPA has issued regulations for inspecting the
On-Board Diagnostic (OBD) system as part of the state emissions inspection. The OBD system is de-
signed to detect engine and transmission problemsthat might cause vehicle emissions to exceed allow-able limits. These inspections apply to all 1996 mod-el year and newer passenger cars and light trucks.
Several states plus the District of Columbia have
opted to start the OBD system inspection prior to
the required EPA regulation effective date of January1, 2002. Other states will add OBD system inspec-
tion in 2002. The inspection of the OBD system consists of a
visual operational check of the “CHECK ENGINE ”
warning light/malfunction indicator lamp (MIL) and
an examination of the OBD system with an electron-ic scan tool while the engine is running. A vehicle passes
the OBD system inspection if
proper the “CHECK ENGINE ” warning light/MIL illu-

Driving tips
8-6
Driving in foreign countries
When planning to use your vehicle in another coun-
try:Confirm the availability of the correct fuel. (Refer
to the “Fuel requirement ” section in chapter 7.)
Comply with all regulations and requirements of
each country. Driving tips for AWD vehicles
All wheel drive distributes the engine power to all
four wheels. AWD vehicles provide better traction
when driving on slippery, wet or snow-covered
roads and when moving out of mud, dirt and sand.
By shifting power between the front and rear wheels,
SUBARU AWD can also provide added traction dur-
ing acceleration and added engine braking forceduring deceleration.
Therefore, your SUBARU AWD vehicle may handle
differently than an ordinary two wheel drive vehicle
and it contains some features unique to AWD. For

Driving tips
8-14
gerous and lead to loss of vehicle control. You must install four winter tires that are of
the same size, construction, brand, and loadrange. Mixing other sizes or constructions
may result in severe mechanical damage to
the drive train of your vehicle and may affect
ride, handling, braking and speedometer/ odometer calibration. It also may be danger-ous and lead to loss of vehicle control. Do not use a combination of radial, belted
bias or bias tires since it may cause danger-ous handling characteristics and lead to an accident.
Your vehicle is equipped with “all season tires ” as
original equipment, which are designed to provide
an adequate measure of traction, handling and
braking performance in year-round driving. In winter,
it may be possible to enhance performance through
use of tires designed specifically for winter drivingconditions.
The optional 17-inch tires for the WRX are summer
tires. Compared with winter and all-season tires,
summer tires give significantly less grip on snowy
and icy road surfaces. Therefore, use of winter tires
is strongly recommended when driving with such
road conditions. When you choose to install winter tires on your ve-
hicle, be sure to use the correct tire size and type.
You must install four winter tires that are of the samesize, construction, brand and load range and you
should never mix radial, belted bias or bias tires
since this may result in dangerous handling charac-
teristics. When you choose a tire, make sure that
there is enough clearance between the tire and ve-
hicle body.
Remember to drive with care at all times regardless
of the type of tires on your vehicle.
Tire chains
Driving on snowy grades or icy roads may require
the use of tire chains, in which case put the chains
on the front wheels only. Use only SAE class S type
chains that are of the correct size for your tires so asnot to damage the vehicle body or suspension.
When driving with tire chains, drive at speeds below 19 mph (30 km/h).
When a temporary spare tire is on a front wheel, re-
place the temporary spare tire with the rear tire onthe same side of the vehicle, and then fit chains on
the front tires.
Always use the utmost care when driving with tire

Maintenance and service
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Tires and wheels Types of tires
You should be familiar with type of tires present on your vehicle.
All season tires
The factory-installed tires on your new vehicle are all
season tires.
All season tires are designed to provide an ade-
quate measure of traction, handling and braking
performance in year-round driving including snowy
and icy road conditions. However all season tires do
not offer as much traction performance as winter
(snow) tires in heavy or loose snow or on icy roads.
All season tires are identified by “ALL SEASON ”
and/or “M+S” (Mud & Snow) on the tire sidewall.
Summer tires
The optional, dealer-installed, 17-inch tires recom-
mended for the WRX are summer tires.
Summer tires are high-speed capability tires best
suited for highway driving under dry conditions.
Summer tires are inadequate for driving on slippery
roads such as on snow-covered or icy roads.
If you drive your vehicle on snow-covered or icy
roads, we strongly recommend the use of winter (snow) tires.
When installing winter tires, be sure to replace all
four tires.
Winter (snow) tires
Winter tires are best suited for driving on snow-cov-
ered and icy roads. However winter tires do not per-
form as well as summer tires and all season tires on
roads other than snow-covered and icy roads.
Tire inspection
Check on a daily basis that the tires are free from serious damage, nails, and stones. At the same
time, check the tires for abnormal wear.
Contact your SUBARU dealer immediately if you find
any problem. NOTE When the wheels and tires strike curbs or are
subjected to harsh treatment as when the vehicle is driven on a rough surface, they can suffer
damage that cannot be seen with the naked eye.This type of damage does not become evident
until time has passed. Try not to drive over curbs, potholes or on other rough surfaces. If
doing so is unavoidable, keep the vehicle ’s
speed down to a walking pace or less, and ap-

Maintenance and service
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After driving approximately 600 miles (1,000 km),
check the wheel nuts again and retighten any nutthat has become loose. Tire replacement
The wheels and tires are important and integral
parts of your vehicle ’s design; they cannot be
changed arbitrarily. The tires fitted as standard
equipment are optimally matched to the characteris-
tics of the vehicle and were selected to give the best
possible combination of running performance, ride
comfort, and service life. It is essential for every tireto have a size and construction matching those
shown on the tire placard and to have a speed sym-
bol and load index matching those shown on the tire
placard.
Using tires of a non-specified size detracts from
controllability, ride comfort, braking performance,
speedometer accuracy and odometer accuracy. It
also creates incorrect body-to-tire clearances and
inappropriately changes the vehicle ’s ground clear-
ance.
All four tires must be the same in terms of manufac-
turer, brand (tread pattern), construction, and size.
You are advised to replace the tires with new ones
that are identical to those fitted as standard equip- ment.
For safe vehicle operation, SUBARU recommends
replacing all four tires at the same time. NOTE
Unidirectional tires: Some tires have a specified direction of rotation. A tire of this type has an ar-
row or other mark on its side wall to indicate thedirection of rotation. Install it so that the direc-tion of rotation is correct when the vehicle isdriven forward.