Subaru WRX STI (2019 year). Manual

(409,1)

北米Model "A1720BE-A" EDITED: 2018/ 3/ 9

Cooling fan, hose and con-
nections

Your vehicle employs an electric cooling
fan which is thermostatically controlled to
operate when the engine coolant reaches
a specific temperature.

Temperature gauge
1)

Normal operating range

If the radiator cooling fan does not operate
even when the engine coolant tempera-
ture gauge exceeds the normal operating
range, the cooling fan circuit may be
defective. Refer to “Temperature gauge”
F3-11.

Check the fuse and replace it if necessary.
Refer to “Fuses” F11-43 and “Fuses and
circuits” F12-10.
If the fuse is not blown, have the cooling

system checked by your SUBARU dealer.

If frequent addition of coolant is necessary,
there may be a leak in the engine cooling
system. It is recommended that the cooling
system and connections be checked for
leaks, damage, or looseness.

Engine coolant

Checking the coolant level

“FULL” level mark

“LOW” level mark

Check the coolant level at each fuel stop.
1. Check the coolant level on the outside
of the reservoir while the engine is cool.
2. If the level is close to or lower than the
“LOW” level mark, add coolant up to the
“FULL” level mark. If the reserve tank is

empty, remove the radiator cap and refill
coolant up to just below the filler neck as
shown in the following illustration.

STI
1)

Fill up to this level

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Maintenance and service/Cooling system

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Except STI
1)

Fill up to this level

3. After refilling the reserve tank and the
radiator, reinstall the cap and check that
the rubber gaskets inside the radiator cap
are in the proper position.

CAUTION

Be careful not to spill engine

coolant when adding it. If coolant
touches the exhaust pipe, it may
cause a bad smell, smoke, and/or
a fire. If engine coolant gets on
the exhaust pipe, be sure to wipe
it off.

Do not splash the engine coolant

over painted parts. The alcohol
contained in the engine coolant
may damage the paint surface.

Changing the coolant

It may be difficult to change the coolant.
Have the coolant changed by your
SUBARU dealer if necessary.

Have the coolant changed according to the
maintenance schedule in the “Warranty
and Maintenance Booklet”.

Air cleaner element

WARNING

Do not operate the engine with the
air cleaner element removed. The air
cleaner element not only filters in-
take air but also stops flames if the
engine backfires. If the air cleaner
element is not installed when the
engine backfires, you could be
burned.

CAUTION

When replacing the air cleaner ele-
ment, use a genuine SUBARU air
cleaner element. If it is not used,
there is the possibility of causing a
negative effect to the engine.

The air cleaner element functions as a filter
screen. When the element is perforated or
removed, engine wear will be excessive
and engine life shortened.

It is not necessary to clean or wash the air
cleaner element.

Maintenance and service/Air cleaner element

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Replacing the air cleaner ele-
ment

Replace the air cleaner element according
to the maintenance schedule in the “War-
ranty and Maintenance Booklet”. Under
extremely dusty conditions, replace it
more frequently. It is recommended that
you always use genuine SUBARU parts.

STI

NOTE

It may be difficult to replace the air
cleaner element. Have the air cleaner
element replaced by your SUBARU
dealer if necessary.

Except STI

Clips

1. Unsnap the two clips holding the air
cleaner case cover.

Air cleaner case

Air cleaner case cover

2. Open the air cleaner case and pull the
cover rearward while lifting it up.

3. Remove the air cleaner element.
4. Clean the inside of the air cleaner case
and case cover with a damp cloth and
install a new air cleaner element.

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Maintenance and service/Air cleaner element

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5. To install the air cleaner case cover,
insert the projections on the air cleaner
case cover into the slits on the air cleaner
case. The illustration above shows an
example in which the projections are not
fitted into the slits correctly.
6. Install in the reverse order of removal.

Spark plugs

It may be difficult to replace the spark
plugs. It is recommended that you have the
spark plugs replaced by your SUBARU
dealer.

Have the spark plugs replaced according
to the maintenance schedule in the “War-
ranty and Maintenance Booklet”.

Recommended spark plugs

For the recommended spark plugs, refer to
“Electrical system” F12-8.

Drive belts

NOTE

For models except STI, it is unneces-
sary to check the deflection of the drive
belt periodically because this engine is
equipped with an automatic belt ten-
sion adjuster. However, have the belt
replaced according to the maintenance
schedule in the “Warranty and Main-
tenance Booklet”. Consult your
SUBARU dealer for replacement.
If the drive belt is loose, cracked or
worn, contact your SUBARU dealer.

Maintenance and service/Spark plugs

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STI
1)

Power steering oil pump pulley

Front side belt

Alternator pulley

Air conditioner compressor pulley

Rear side belt

Crank pulley

22 lbf (98 N, 10 kgf)

CAUTION

The front side belt, which runs in
conjunction with the following com-
ponents, must be used within the
specified deflection.

Power steering oil pump pulley

Alternator pulley

Crank pulley

Check the deflection of the front side

belt and if there is any looseness,
cracks, wear or unusual noise on the
front side belt, contact your
SUBARU dealer.

Continuing to use the vehicle with
the belt outside of the specification
may cause the engine to malfunc-
tion and the above components to
malfunction.

To check the deflection of the front side
belt, place a straightedge (ruler) across
two adjacent pulleys (alternator pulley and
crank pulley) and apply a force of 22 lbf (98
N, 10 kgf) midway between the pulleys by
using a spring scale. The belt deflection
should be the amount specified. If the front
side belt is loose, cracked or worn, contact
your SUBARU dealer.

in (mm)

Deflection

New belt

Used belt

0.28 – 0.35

(7.0 – 9.0)

0.35 – 0.43
(9.0 – 11.0)

The rear side belt is a stretch-type belt,
therefore the deflection does not need to
be checked. If there are cracks or wear
confirmed on the belts and a squeaking
noise is heard from them, contact your
SUBARU dealer.

Manual transmission oil

It is not necessary to check the transmis-
sion oil level. Check that there are no
cracks, damage or leakage. However,
have the oil inspected by your SUBARU
dealer according to the maintenance
schedule in the “Warranty and Mainte-
nance Booklet”. Consult your SUBARU
dealer for details.

Recommended grade and
viscosity

Each oil manufacturer has its own base
oils and additives. Never use different
brands together. For details, refer to
“Manual transmission, front differential
and rear differential gear oil” F12-6.

Maintenance and service/Manual transmission oil

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Continuously variable trans-
mission fluid

It is not necessary to check the transmis-
sion fluid level. Check that there are no
cracks, damage or leakage. However,
have the fluid inspected by your SUBARU
dealer according to the maintenance
schedule in the “Warranty and Mainte-
nance Booklet”. Consult your SUBARU
dealer for details.

Front differential gear oil
(CVT models) and rear differ-
ential gear oil

It is not necessary to check the gear oil
level. Check that there are no cracks,
damage or leakage. However, have the oil
inspected by your SUBARU dealer ac-
cording to the maintenance schedule in
the “Warranty and Maintenance Booklet”.
Consult your SUBARU dealer for details.

Recommended grade and
viscosity

CAUTION

Using a differential gear oil other
than the specified oil may cause a
decline in vehicle performance.

Power steering fluid (STI)

Checking the fluid level

The power steering fluid expands greatly
as its temperature rises; the fluid level
differs according to fluid temperature.
Therefore, the reservoir tank has two
different checking ranges for hot and cold
fluids.

Check the power steering fluid level
monthly.
1. Park the vehicle on a level surface, and
stop the engine.
2. Check the fluid level of the reservoir
tank.
When the fluid is hot after the vehicle has
been run: Check that the oil level is
between “HOT MIN” and “HOT MAX” on

Maintenance and service/Continuously variable transmission fluid

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the surface of the reservoir tank.
When the fluid is cool before the vehicle is
run: Check that the oil level is between
“COLD MIN” and “COLD MAX” on the
surface of the reservoir tank.
3. If the fluid level is lower than the
applicable “MIN” line, add the recom-
mended fluid as necessary to bring the
level between the “MIN” and “MAX” line.

If the fluid level is extremely low, it may
indicate possible leakage. Consult your
SUBARU dealer for an inspection.

WARNING

Be careful not to burn yourself
because the fluid may be hot.

CAUTION

When you add power steering

fluid, use only clean fluid, and
be careful not to allow any dirt
into the tank. And never use
different brands together.

Be careful not to spill power

steering fluid when adding it. If
power steering fluid touches the
exhaust pipe, it may cause a bad
smell, smoke, and/or a fire. If
power steering fluid gets on the

exhaust pipe, be sure to wipe it
off.

Recommended fluid

Refer to “Fluids” F12-7.

Brake fluid

Checking the fluid level

WARNING

Never let brake fluid contact your

eyes because brake fluid can be
harmful to your eyes. If brake
fluid gets in your eyes, immedi-
ately flush them thoroughly with
clean water. For safety, when
performing this work, wearing
eye protection is advisable.

Brake fluid absorbs moisture

from the air. Any absorbed moist-
ure can cause a dangerous loss
of braking performance.

If the vehicle requires frequent

refilling, there may be a leak. If
you suspect a problem, have the
vehicle checked at your SUBARU
dealer.

CAUTION

When adding brake fluid, be care-

ful not to allow any dirt into the
reservoir.

Never splash the brake fluid over

painted surfaces or rubber parts.

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Maintenance and service/Brake fluid

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Alcohol contained in the brake
fluid may damage them.

Be careful not to spill brake fluid

when adding it. If brake fluid
touches the exhaust pipe, it may
cause a bad smell, smoke, and/or
a fire. If brake fluid gets on the
exhaust pipe, be sure to wipe it
off.

“MAX” level line

Check the brake fluid level in this area.

“MIN” level line

Check the fluid level monthly.
Check the fluid level on the outside of the
reservoir. Because this reservoir is used
for both the brake and clutch systems and
has chambers for each system, be sure to
check the fluid level for the brake system at

the front part of the reservoir (shaded
area in the illustration). If the fluid level is
below “MIN”, add the recommended brake
fluid to “MAX”.
Use only brake fluid from a sealed contain-
er.

Recommended brake fluid

Refer to “Fluids” F12-7.

CAUTION

Never use different brands of brake
fluid together. Also, avoid mixing
DOT 3 and DOT 4 brake fluids even if
they are the same brand.

Clutch fluid (MT models)

Checking the fluid level

WARNING

Never let clutch fluid contact your
eyes because clutch fluid can be
harmful to your eyes. If clutch fluid
gets in your eyes, immediately flush
them thoroughly with clean water.
For safety, when performing this
work, wearing eye protection is
advisable.

CAUTION

Clutch fluid absorbs moisture

from the air. Any absorbed moist-
ure can cause improper clutch
operation.

If the vehicle requires frequent

refilling, there may be a leak. If
you suspect a problem, have the
vehicle checked at your SUBARU
dealer.

When you add clutch fluid, be

careful not to allow any dirt into
the tank.

Never splash the clutch fluid over

painted surfaces or rubber parts.

Maintenance and service/Clutch fluid (MT models)

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Alcohol contained in the clutch
fluid may damage them.

Be careful not to spill clutch fluid

when adding it. If clutch fluid
touches the exhaust pipe, it may
cause a bad smell, smoke, and/or
a fire. If clutch fluid gets on the
exhaust pipe, be sure to wipe it
off.

Check the fluid level for the clutch

system at the inboard side of the
reservoir. You cannot check the
fluid level at the outboard side of
the reservoir.

“MAX” level line

Check the clutch fluid level in this area.

“MIN” level line

Check the fluid level monthly.

Check the fluid level on the outside of the
reservoir. Because this reservoir is used
for both the brake and clutch systems and
has chambers for each system, be sure to
check the fluid level for the clutch system
at the inboard side of the reservoir
(shaded area in the illustration). If the fluid
level is below “MIN”, add the recom-
mended clutch fluid to “MAX”.
Use only clutch fluid from a sealed contain-
er.

Recommended clutch fluid

Refer to “Fluids” F12-7.

CAUTION

Never use different brands of clutch
fluid together. Also, avoid mixing
DOT 3 and DOT 4 brake fluids even if
they are the same brand.

Brake booster

If the brake booster does not operate as
described in the following, have it checked
by your SUBARU dealer.
1. With the engine off, depress the brake
pedal several times, applying the same
pedal force each time. The distance the
pedal travels should not vary.
2. With the brake pedal depressed, start
the engine. The pedal should move slightly
down to the floor.
3. With the brake pedal depressed, stop
the engine and keep the pedal depressed
for 30 seconds. The pedal height should
not change.
4. Start the engine again and run for
approximately one minute then turn it off.
Depress the brake pedal several times to
check the brake booster. The brake
booster operates properly if the pedal
stroke decreases with each depression.

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Maintenance and service/Brake booster

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NOTE

When you depress the brake pedal
strongly or suddenly, you might feel
that lighter depression of the brake
pedal generates a greater braking
force. However, even though these
occur, they do not indicate any mal-
functions, and the brake assist system
is operating properly.

Brake assist is not a system that brings
more braking ability to the vehicle
beyond its breaking capability.

Brake pedal

Check the brake pedal free play and
reserve distance according to the main-
tenance schedule in the “Warranty and
Maintenance Booklet”.

Checking the brake pedal free
play

0.02 – 0.11 in (0.5 – 2.7 mm)

Stop the engine and firmly depress the
brake pedal several times. Lightly pull the
brake pedal up with one finger to check the
free play with a force of less than 2 lbf (10
N, 1 kgf).
If the free play is not within proper
specification, contact your SUBARU deal-
er.

Checking the brake pedal re-
serve distance

More than 2.56 in (65 mm)

Depress the pedal with a force of approxi-
mately 66 lbf (294 N, 30 kgf) and measure
the distance between the upper surface of
the pedal pad and the floor.
When the measurement is smaller than
the specification, or when the pedal does
not operate smoothly, contact with your
SUBARU dealer.

Maintenance and service/Brake pedal

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Clutch pedal (MT models)

Check the clutch pedal free play according
to the maintenance schedule in the “War-
ranty and Maintenance Booklet”.

Checking the clutch function

Check the clutch engagement and disen-
gagement.
1. With the engine idling, check that there
are no abnormal noises when the clutch
pedal is depressed, and that shifting into
1st or reverse feels smooth.
2. Start the vehicle by releasing the pedal
slowly to check that the engine and
transmission smoothly couple without
any sign of slippage.

Checking the clutch pedal
free play

0.16 – 0.43 in (4.0 – 11.0 mm)

Lightly depress the clutch pedal down with
your finger until you feel resistance, and
check the free play.
If the free play is not within proper
specification, contact your SUBARU deal-
er.

Hill start assist system

Ensure that the Hill start assist system
operates properly under the following
circumstances.
1. Stop the vehicle on an uphill grade by
depressing the brake pedal (all models)
and clutch pedal (MT models only), with
the engine running.
2. Make sure that the vehicle does not
move backward for several seconds after
the brake pedal is released.
3. Then make sure the vehicle starts
climbing the grade by following the normal
starting procedures.

If the Hill start assist system does not
operate as described above, contact your
SUBARU dealer.

Maintenance and service/Clutch pedal (MT models)

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Replacement of brake pad
and lining

The disc brakes have audible wear in-
dicators on the brake pads. If the brake
pads wear close to their service limit, the
wear indicator makes a very audible
scraping noise when the brake pedal is
applied.

If you hear this scraping noise each time
you apply the brake pedal, have the brake
pads serviced by your SUBARU dealer as
soon as possible.

CAUTION

It is recommended that you dis-

connect the vehicle battery be-
fore replacing the brake pad.
However, it is dangerous to dis-
connect the vehicle battery. We
recommend that you have your
SUBARU dealer replace the brake
pad.

If you continue to drive despite

the scraping noise from the audi-
ble brake pad wear indicator, it
will result in the need for costly
brake rotor repair or replace-
ment.

Breaking-in of new brake
pads (models with electronic
parking brake system)

When replacing the brake pad, use only
genuine SUBARU parts. After replace-
ment, break in the new parts as follows.

Brake pad

While maintaining a speed of 30 to 40 mph
(50 to 65 km/h), step on the brake pedal
lightly. Repeat this five or more times. Also,
apply and release the electronic parking
brake five or more times.

Breaking-in of new brake
pads and linings (models
without electronic parking
brake system)

When replacing the brake pad or lining,
use only genuine SUBARU parts. After
replacement, break in the new parts as
follows.

Brake pad and lining

While maintaining a speed of 30 to 40 mph
(50 to 65 km/h), step on the brake pedal
lightly. Repeat this five or more times.

Parking brake lining

1. Drive the vehicle at a speed of approxi-
mately 22 mph (35 km/h).
2. With the parking brake release button
pushed in, pull the parking brake lever
SLOWLY and GENTLY (pulling with a
force of approximately 33.7 lbf [150 N,
15.3 kgf]).
3. Drive the vehicle for approximately 220
yards (200 meters) in this condition.
4. Wait 5 to 10 minutes for the parking
brake to cool down. Repeat this proce-
dure.
5. Check the parking brake stroke. If the
parking brake stroke is out of the specified
range, adjust it by turning the adjusting nut
located on the parking brake lever.

Maintenance and service/Replacement of brake pad and lining

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Parking brake stroke:

7 – 8 notches / 45 lbf (200 N, 20.4 kgf)

WARNING

Select a safe location and situation
for break-in driving.

CAUTION

Pulling the parking brake lever too
forcefully may cause the rear wheels
to lock. To avoid this, be certain to
pull the lever up slowly and gently.

Parking brake stroke (models
without electronic parking
brake system)

Check the parking brake stroke according
to the maintenance schedule in the “War-
ranty and Maintenance Booklet”.

When the parking brake is properly ad-
justed, braking power is fully applied by
pulling the lever up 7 to 8 notches gently
but firmly (approximately 45 lbf [200 N,
20.4 kgf]). If the parking brake lever stroke
is not within the specified range, have the
brake system checked and adjusted at
your SUBARU dealer.

Tires and wheels

Types of tires

You should be familiar with type of tires
present on your vehicle.

All season tires

All season tires are designed to provide an
adequate 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

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.

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Maintenance and service/Parking brake stroke (models without electronic parking brake system)

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Winter (snow) tires

Winter tires are best suited for driving on
snow-covered and icy roads. However
winter tires do not perform as well as
summer tires and all season tires on roads
other than snow-covered and icy roads.

Tire pressure monitoring
system (TPMS) (if equipped)

The tire pressure monitoring system pro-
vides the driver with a warning message by
sending a signal from a sensor that is
installed in each wheel when tire pressure
is severely low. The tire pressure monitor-
ing system will activate only when the
vehicle is driven. Also, this system may not
react immediately to a sudden drop in tire
pressure (for example, a blow-out caused
by running over a sharp object).

Low tire pressure warning light

If you adjust the tire pressures in a warm
garage and will then drive the vehicle in
cold outside air, the resulting drop in tire
pressures may cause the low tire pressure
warning light to illuminate. To avoid this
problem when adjusting the tire pressures
in a warm garage, inflate the tires to
pressures higher than those shown on
the tire placard. Specifically, inflate them
by an extra 1 psi (6.9 kPa, 0.07 kgf/cm

) for

every difference of 108F (5.68C) between
the temperature in the garage and the
temperature outside. By way of example,
the following table shows the required tire
pressures that correspond to various out-
side temperatures when the temperature
in the garage is 608F (15.68C).

Example:
Tire size: 245/40R18 97W
Standard tire pressures:
Front: 33 psi (230 kPa, 2.3 kgf/cm

)

Rear: 32 psi (220 kPa, 2.2 kgf/cm

)

Garage temperature: 608F (15.68C)

Outside

temperature

Adjusted pressure

[psi (kPa, kgf/cm

)]

Front

Rear

308F (−18C)

36 (250, 2.5)

35 (240, 2.4)

108F (−128C)

38 (260, 2.6)

37 (255, 2.55)

−108F (−238C) 40 (275, 2.75)

39 (270, 2.7)

If the low tire pressure warning light
illuminates when you drive the vehicle in
cold outside air after adjusting the tire
pressures in a warm garage, re-adjust the
tire pressures using the method described
above. Then, increase the vehicle speed
to at least 20 mph (32 km/h) and check to
see that the low tire pressure warning light
turns off a few minutes later. If the low tire
pressure warning light does not turn off,
the tire pressure monitoring system may
not be functioning normally. In this event,
go to a SUBARU dealer to have the
system inspected as soon as possible.

While the vehicle is driven, friction be-
tween tires and the road surface causes
the tires to warm up. After illumination of

Maintenance and service/Tires and wheels

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the low tire pressure warning light, any
increase in the tire pressures caused by an
increase in the outside air temperature or
by an increase in the temperature in the
tires can cause the low tire pressure
warning light to turn off.

System resetting is necessary when the
wheels are changed (for example, a switch
to snow tires) and new TPMS valves are
installed on the newly fitted wheels. Have
this work performed by a SUBARU dealer
following wheel replacement.

It may not be possible to install TPMS
valves on certain wheels that are on the
market. Therefore, if you change the
wheels (for example, a switch to snow
tires), use wheels that have the same part
number as the standard-equipment
wheels. Without four operational TPMS
valve/sensors on the wheels, the TPMS
will not fully function and the warning light
on the combination meter will illuminate
steadily after blinking for approximately
one minute.

When a tire is replaced, adjustments are
necessary to ensure continued normal
operation of the tire pressure monitoring
system. As with wheel replacement, there-
fore, you should have the work performed
by a SUBARU dealer.

WARNING

If the low tire pressure warning light
does not illuminate briefly after the
ignition switch is turned ON or the
light illuminates steadily after blink-
ing for approximately one minute,
you should have your Tire Pressure
Monitoring System checked at a
SUBARU dealer as soon as possi-
ble.

If this light illuminates while driving,
never brake suddenly. Instead, per-
form the following procedure. Other-
wise an accident involving serious
vehicle damage and serious perso-
nal injury could occur.

1) Keep driving straight ahead while

gradually reducing speed.

2) Slowly pull off the road to a safe

place.

If this light still illuminates while
driving after adjusting the tire pres-
sure, a tire may have significant
damage and a fast leak that causes
the tire to lose air rapidly. If you have
a flat tire, refer to “Flat tires” F9-4.

When a spare tire is mounted or a
wheel rim is replaced without the
original pressure sensor/transmitter
being transferred, the low tire pres-

sure warning light will illuminate
steadily after blinking for approxi-
mately one minute. This indicates
the TPMS is unable to monitor all
four road wheels. Contact your
SUBARU dealer as soon as possible
for tire and sensor replacement and/
or system resetting. If the light
illuminates steadily after blinking
for approximately one minute,
promptly contact a SUBARU dealer
to have the system inspected.

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 im-
mediately 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

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Maintenance and service/Tires and wheels

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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 approach the curbs as
squarely as possible. Also, make
sure the tires are not pressed
against the curb when you park
the vehicle.

If you feel unusual vibration

while driving or find it difficult to
steer the vehicle in a straight line,
one of the tires and/or wheels
may be damaged. Drive slowly to
the nearest authorized SUBARU
dealer and have the vehicle in-
spected.

Tire pressures and wear

Maintaining the correct tire pres-
sures helps to maximize the tires’
service lives and is essential for
good running performance. Check
and, if necessary, adjust the pres-
sure of each tire (including the
spare) at least once a month (for
example, during a fuel stop) and
before any long journey.

Tire placard

Check the tire pressures when the
tires are cold. Use a pressure
gauge to adjust the tire pressures
to the values shown on the tire
placard. The tire placard is located

on the door pillar on the driver’s
side.

Driving even a short distance
warms up the tires and increases
the tire pressures. Also, the tire
pressures are affected by the out-
side temperature. It is best to check
tire pressure outdoors before driv-
ing the vehicle.

When a tire becomes warm, the air
inside it expands, causing the tire
pressure to increase. Be careful not
to mistakenly release air from a
warm tire to reduce its pressure.

Maintenance and service/Tires and wheels

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Subaru WRX STI (2019 year). Manual - part 25