2006 SUBARU IMPREZA check engine

7-8 Starting and operating
ing.
1) Turn the ignition switch to the “OFF ”
position and wait for at least 10 sec-
onds. After checking that the parking
brake is firmly set, turn the ignition
switch to the “START ” position while de-
pressing the accelerator pedal slightly
(approximately a quarter of the full
stroke). Release the accelerator pedal
as soon as the engine starts.
2) If this fails to start the engine, turn the
ignition switch back to the “OFF ” posi-
tion and wait for at least 10 seconds.
Then fully depress the accelerator ped-
al and turn the ignition switch to the“ START ” position. If the engine starts,
quickly release the accelerator pedal.
3) If this fails to start the engine, turn the
ignition switch again to the “OFF ” posi-
tion. After waiting for 10 seconds or
longer, turn the ignition switch to the“ START ” position without depressing
the accelerator pedal.
4) If the engine still refuses to start, con-
tact your nearest SUBARU dealer for
assistance.
6. Confirm that all warning and indicator
lights have gone out after the engine has
started. The fuel injection system auto-
matically lowers the idle speed as the en-
gine warms up.
While the engine is warming up, make sure that the selector lever is at the
“P ” or
“ N ” position and that the parking brake is
applied.
NOTE
The engine may be difficult to start
when the battery has been disconnect-
ed and reconnected (for maintenance
or other purposes). This difficulty is
caused by the electronically controlled
throttle ’s self-diagnosis function. To
overcome it, keep the ignition switch in
the “ON ” position for approximately 10
seconds before starting the engine.
Stopping the engine
The ignition switch should be turned off
only when the vehicle is stopped and the
engine is idling.
If you restart the engine while the
vehicle is moving, shift the selector
lever into the “N ” position. Do not
attempt to place the selector lever of
a moving vehicle into the “P ” posi-
tion.
Do not stop the engine when the ve-
hicle is moving. This will cause loss
of power to the power steering and
the brake booster, making steering
and braking more difficult. It could
also result in accidental activation
of the “LOCK ” position on the igni-
tion switch, causing the steering
wheel to lock.

7-22 Starting and operating
Disc brake pad wear warning
indicators
The disc brake pad wear warning indica-
tors on the disc brakes give a warning
noise when the brake pads are worn.
If a squeaking or scraping noise is heard
from the disc brakes while braking, imme-
diately have your vehicle checked by your
SUBARU dealer.
ABS (Anti-lock Brake Sys-
tem)
The ABS system prevents the lock-up of
wheels which may occur during sudden
braking or braking on slippery road surfac-
es. This helps prevent the loss of steering
control and directional stability caused by
wheel lock-up.
When the ABS system is operating, you
may hear a chattering noise or feel a slight
vibration in the brake pedal. This is normal
when the ABS operates.
The ABS system will not operate when the
vehicle speed is below approximately 6
mph (10 km/h).
ABS system self-check
Just after the vehicle is started, you may
feel on the brake pedal a vibration similar
to when the ABS operates, and you may
also hear the sound of the ABS working
from the engine compartment. This is
caused by an automatic functional test of
the ABS system being carried out and
700040
Always use the utmost care in driv-
ing – overconfidence because you
are driving with an ABS equipped
vehicle could easily lead to a seri-
ous accident.
The ABS system does not always
decrease stopping distance. You
should always maintain a safe fol-
lowing distance from other vehi-
cles.
When driving on badly surfaced
roads, gravel roads, icy roads, or
over deep newly fallen snow,
stopping distances may be longer
for a vehicle with the ABS system
than one without. When driving
under these conditions, therefore,
reduce your speed and leave am-
ple distance from other vehicles.
When you feel the ABS system
operating, you should maintain
constant brake pedal pressure.
Do not pump the brake pedal
since doing so may defeat the op-
eration of the ABS system.

7-24 Starting and operating
Electronic Brake Force Dis-
tribution (EBD) system
The EBD system maximizes the effective-
ness of the brakes by allowing the rear
brakes to supply a greater proportion of
the braking force. It functions by adjusting
the distribution of braking force to the rear
wheels in accordance with the vehicle ’s
loading condition and speed.
The EBD system is an integral part of the
ABS system and uses some of the ABS
system ’s components to perform its func-
tion of optimizing the distribution of brak-
ing force. If any of the ABS components
used by the EBD function fails, the EBD
system also stops working.
When the EBD system is operating, you
may hear a chattering noise or feel a slight
vibration in the brake pedal. This is normal
and does not indicate a malfunction.
Steps to take if EBD system
fails
If a malfunction occurs in the EBD system,
the system stops working and the brake
system warning light and ABS warning
light come on simultaneously.
The EBD system may be faulty if the brake
system warning light and ABS warning
light illuminate simultaneously during driv-
ing.
Even if the EBD system fails, the conven-
tional braking system will still function.
However, the rear wheels will be more
prone to locking when the brakes are ap-
plied harder than usual and the vehicle ’s
motion may therefore become somewhat
harder to control.
If the brake system warning light and ABS warning light illuminate simultaneously,
take the following steps:
1. Stop the vehicle in the nearest safe, flat
place.
2. Shut down the engine, then restart it.
3. Release the parking brake. If both
warning lights go out, the EBD system
may be faulty. Drive carefully to the near-
est SUBARU dealer and have the system
inspected.
4. If both warning lights come on again
and stay illuminated after the engine has
been restarted, shut down the engine
again, apply the parking brake, and check
the brake fluid level.
5. If the brake fluid level is not below the“
MIN ” mark, the EBD system may be
faulty. Drive carefully to the nearest
SUBARU dealer and have the system in-
spected.
6. If the brake fluid level is below the“ MIN ” mark, DO NOT drive the vehicle. In-
stead, have the vehicle towed to the near-
est SUBARU dealer for repair.
700360

Driving tips 8-3
– CONTINUED –
NOTE
Due to the expansion and contraction
of the metals used in the manufacture
of the exhaust system, you may hear a
crackling sound coming from the ex-
haust system for a short time after the
engine has been shut off. This sound is
normal.
Catalytic converter
Turbo models
Non-turbo modelsThe catalytic converter is installed in the
exhaust system. It serves as catalyst to
reduce HC, CO and NOx in exhaust gas-
es, thus providing cleaner exhaust.
To avoid damage to the catalytic convert-
er:
Use only unleaded fuel. Even a small
amount of leaded fuel will damage the cat-
alytic converter.
Never start the engine by pushing or
pulling the vehicle.
Avoid racing the engine.
Never turn off the ignition switch while
the vehicle is moving.
Keep your engine tuned-up. If you feel
the engine running rough (misfiring, back-
firing or incomplete combustion), have
your vehicle checked and repaired by an
authorized SUBARU dealer.
Do not apply undercoating or rust pre-
vention treatment to the heat shield of cat-
alytic converter and the exhaust system.
If at any time you suspect that ex-
haust fumes are entering the vehi-
cle, have the problem checked
and corrected as soon as possi-
ble. If you must drive under these
conditions, drive only with all win-
dows fully open.
Keep the trunk lid (Sedan) or rear
gate (Wagon) closed while driving
to prevent exhaust gas from en-
tering the vehicle.
800232
800218
Avoid fire hazards. Do not drive or
park the vehicle anywhere near
flammable materials (e.g. grass,
paper, rags or leaves), because
the catalytic converter operates at
very high temperatures.

Driving tips 8-5
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 during acceleration and
added engine braking force during decel-
eration.
Therefore, your SUBARU AWD vehicle
may handle differently than an ordinary
two wheel drive vehicle and it contains
some features unique to AWD. For safety
purposes as well as to avoid damaging
the AWD system, you should keep the fol- lowing tips in mind:
An AWD vehicle is better able to climb
steeper roads under snowy or slippery
conditions than a two wheel drive vehicle.
There is little difference in handling, how-
ever, during extremely sharp turns or sud-
den braking. Therefore, when driving
down a slope or turning corners, be sure
to reduce your speed and maintain an am-
ple distance from other vehicles.
When replacing a tire, make sure you
use only the same size, construction,
brand, and load range as the original tires
listed on the tire placard. Using other siz-
es, circumference or construction may re-
sult in severe mechanical damage to the
drive train of your vehicle and may affect
ride, handling, braking, speedometer/
odometer calibration, and clearance be-
tween the body and tires. It also may be
dangerous and lead to loss of vehicle con-
trol.
If you use a temporary spare tire to re-
place a flat tire, be sure to use the original
temporary spare tire stored in the vehicle.
Using other sizes may result in severe
mechanical damage to the drive train of
your vehicle.
Always check the cold tire pressure be-
fore starting to drive. The recommended
tire pressure is provided on the tire plac-
ard, which is located under the door latch on the driver
’s side.
Tire chains should always be placed on
the front wheels only.
There are some precautions that you
must observe when towing your vehicle.
For detail information, see the “Towing ”
section in chapter 9.
800004
Always maintain a safe driving
speed according to the road and
weather conditions in order to
avoid having an accident on a
sharp turn, during sudden braking
or under other similar conditions.
Always use the utmost care in
driving – overconfidence because
you are driving an All-Wheel Drive
vehicle could easily lead to a seri-
ous accident.

Driving tips 8-7
with your fingers and thumbs on the out-
side of the rim.
If driving through water, such as when
crossing shallow streams, first check the
depth of the water and the bottom of the
stream bed for firmness and ensure that
the bed of the stream is flat. Drive slowly
and completely through the stream. The
water should be shallow enough that it
does not reach the vehicle ’s undercar-
riage. Water entering the engine air intake
or the exhaust pipe or water splashing
onto electrical parts may damage your ve-
hicle and may cause it to stall. Never at-
tempt to drive through rushing water; re-
gardless of its depth, it can wash away the
ground from under your tires, resulting in
possible loss of traction and even vehicle
rollover.
Always check your brakes for effective-
ness immediately after driving in sand,
mud or water. Do this by driving slowly
and stepping on the brake pedal. Repeat
that process several times to dry out the
brake discs and brake pads.
Do not drive or park over or near flam-
mable materials such as dry grass or fall-
en leaves, as they may burn easily. The
exhaust system is very hot while the en-
gine is running and right after the engine
stops. This could create a fire hazard.
After driving through tall grass, mud, rocks, sand, rivers, etc., check that there
is no grass, bush, paper, rags, stones,
sand, etc. adhering to or trapped on the
underbody. Clear off any such matter from
the underbody. If the vehicle is used with
these materials trapped or adhering to the
underbody, a mechanical breakdown or
fire could occur.
Secure all cargo carried inside the vehi-
cle and make certain that it is not piled
higher than the seatbacks. During sudden
stops or jolts, unsecured cargo could be
thrown around in the vehicle and cause in-
jury. Do not pile heavy loads on the roof.
Those loads raise the vehicle ’s center of
gravity and make it more prone to tip over.
If you must rock the vehicle to free it
from sand or mud, depress the accelera-
tor pedal slightly and move the selector le-
ver back and forth between “D ” and “R ” re-
peatedly. Do not race the engine. For the
best possible traction, avoid spinning the
wheels when trying to free the vehicle.
When the road surface is extremely slip-
pery, you can obtain better traction by
starting the vehicle with the transmission
in 2nd than 1st (both for MT and AT).
Never equip your vehicle with tires larg-
er than those specified in this manual.
Frequent driving of an AWD vehicle un-
der hard-driving conditions such as rough
roads or off roads will necessitate more frequent replacement of engine oil, brake
fluid and transmission oil than that speci-
fied in the maintenance schedule de-
scribed in the
“Warranty and Maintenance
Booklet ”.
Remember that damage done to your
Subaru while operating it off-road and not
using common sense precautions such as
those listed above is not eligible for war-
ranty coverage.
Wash the vehicle ’s underbody after off-
road driving. Suspension components are
particularly prone to dirt buildup, so they
need to be washed thoroughly.

8-8 Driving tips
Winter driving
Operation during cold weath-
er
Carry some emergency equipment, such
as tire chains, a window scraper, a bag of
sand, flares, a small shovel, and jumper
cables.
Check the battery and cables. Cold tem-
peratures reduce battery capacity. The
battery must be in good condition to pro-
vide enough power for cold winter starts.
Use an engine oil of proper grade and vis-
cosity for cold weather. Heavy summer oil
will cause harder starting.
Keep the door locks from freezing by squirting them with deicer or glycerin.
Forcing a frozen door open may damage
or separate the rubber weather strips
around the door. If the door is frozen, use
hot water to melt the ice, and afterwards
thoroughly wipe the water away.
Use a windshield washer fluid that con-
tains an antifreeze solution. Do not use
engine antifreeze or other substitutes be-
cause they may damage the paint of the
vehicle.
SUBARU Windshield Washer Fluid con-
tains 58.5% methyl alcohol and 41.5%
surfactant, by volume. Its freezing temper-
ature varies according to how much it is di-
luted, as indicated in the following table.
In order to prevent freezing of washer flu-
id, check the freezing temperatures in the
table above when adjusting the fluid con-
centration to the outside temperature.
If you fill the reservoir tank with a fluid with
a different concentration from the one
used previously, purge the old fluid fromthe piping between the reservoir tank and
washer nozzles by operating the washer
for a certain period of time. Otherwise, if
the concentration of the fluid remaining in
the piping is too low for the outside tem-
perature, it may freeze and block the noz-
zles.
Before driving your vehicle
Before entering the vehicle, remove any
snow or ice from your shoes because that
could make the pedals slippery and dan-
gerous.
While warming up the vehicle before driv-
ing, check that the accelerator pedal,
brake pedal, and all other controls operate
smoothly.
Clear away ice and snow that has accu-
mulated under the fenders to avoid mak-
ing steering difficult. During severe winter
driving, stop when and where it is safe to
800259
Washer Fluid
Concentration Freezing
Temperature
30% 10.4 F ( –12 C)
50% –4F ( –20 C)
100% –49 F ( –45 C)
Adjust the washer fluid concentra-
tion appropriately for the outside
temperature. If the concentration is
inappropriate, sprayed washer fluid
may freeze on the windshield and
obstruct your view, and the fluid
may freeze in the reservoir tank.

Driving tips 8-9
– CONTINUED –
do so and check under the fenders period-
ically.
Parking in cold weather
Do not use the parking brake when park-
ing for long periods in cold weather since
it could freeze in that position. Instead, ob-
serve the following.
1. Place the shift lever in “1 ” or “R ” for
manual transmission vehicles, and in “P ”
for automatic transmission vehicles.
2. Use tire stops under the tires to prevent
the vehicle from moving.
When the vehicle is parked in snow or
when it snows, raise the wiper blades off
the glass to prevent damage to them.
When the vehicle has been left parked af-
ter use on roads heavily covered with
snow, or has been left parked during a
snowstorm, icing may develop on the
brake system, which could cause poor
braking action. Check for snow or ice
buildup on the suspension, disc brakes
and brake hoses underneath the vehicle.
If there is caked snow or ice, remove it,
being careful not to damage the disc
brakes and brake hoses and ABS har-
ness.
Refueling in cold weather
To help prevent moisture from forming in
the fuel system and the risk of its freezing,
use of an antifreeze additive in the fuel
tank is recommended during cold weath-
er.
Use only additives that are specifically de-
signed for this purpose. When an anti-
freeze additive is used, its effect lasts
longer if the tank is refilled whenever the
fuel level reaches half empty.
If your SUBARU is not going to be used for
an extended period, it is best to have the
fuel tank filled to capacity.
Driving on snowy and icy
roads
To prevent skidding and slipping, avoid
sudden braking, abrupt acceleration, high-
speed driving, and sharp turning when
driving on snowy or icy roads.
Always maintain ample distance between your vehicle and the vehicle ahead of you
to avoid the need for sudden braking.
To supplement the foot brake, use the en-
gine brake effectively to control the vehi-
cle speed. (Shift into a lower gear when
necessary.)
Avoid shifting down abruptly. Such behav-
ior can cause the wheels to lock, possibly
leading to loss of vehicle control.
An anti-lock brake system (ABS) enhanc-
es your vehicle
’s braking performance on
snowy and icy roads. Refer to the “ABS
(Anti-lock Brake System) ” section in chap-
ter 7 for information on braking on slippery
surfaces.
NOTE
The following tires are summer tires.
Compared with winter and all-season
tires, summer tires give significantly
less grip on snowy and icy road surfac-
es. Avoid driving on snowy and icy
road surface with summer tires.
225/45R17 tires for WRX-STI
Snow can trap dangerous exhaust
gases under your vehicle. Keep
snow clear of the exhaust pipe and
from around your vehicle if you park
the vehicle in snow with the engine
running.
Do not use the cruise control on
slippery roads such as snowy or icy
roads. This may cause loss of vehi-
cle control.