2012 SUBARU IMPREZA WRX STI check engine

Black plate (341,1)
北米Model "A1130BE-A" EDITED: 2011/ 6/ 7
mended engine oil for optimum engine
performance. Conventional oil may be
used if synthetic oil is unavailable.
Cooling system
WARNING
Never attempt to remove the radia-
tor cap until the engine has been
shut off and has cooled down
completely. Since the coolant is
under pressure, you may suffer
serious burns from a spray of boil-
ing hot coolant when the cap is
removed.
CAUTION
. Vehicles are filled at the factory
with SUBARU Super Coolant that
does not require the first change
for 11 years/137,500 miles (11
years/220,000 km). This coolant
should not be mixed with any
other brand or type of coolant
during this period. Mixing with a
different coolant will reduce the
life of the coolant. Should it be
necessary to top up the coolant
for any reason, use only
SUBARU Super Coolant.
If the SUBARU Super Coolant is
diluted with another brand or
type, the maintenance interval is shortened to that of the mixing
coolant.
. Do not splash the engine coolant
over painted parts. The alcohol
contained in the engine coolant
may damage the paint surface.
& Cooling fan, hose and con-
nectionsYour vehicle employs an electric cooling
fan which is thermostatically controlled to
operate when the engine coolant reaches
a specific temperature.
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 ”
F 3-10.
Check the fuse and replace it if necessary.
Refer to “Fuses”F 11-37 and “Fuse panel
located in the engine compartment” F12-
12.
If the fuse is not blown, have the cooling
system checked by your SUBARU dealer.
If frequent addition of coolant is neces-
sary, 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.
Maintenance and service
11-11
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11

Black plate (342,1)
北米Model "A1130BE-A" EDITED: 2011/ 6/ 7
11-12
Maintenance and service
& Engine coolant! Checking the coolant level
WARNING
Never attempt to remove the radia-
tor cap until the engine has been
shut off and has cooled down
completely. Since the coolant is
under pressure, you may suffer
serious burns from a spray of boil-
ing hot coolant when the cap is
removed.1) “FULL ”level mark
2) “LOW ”level markCheck 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
as required.
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.
WARNING
Never attempt to remove the radia-
tor cap until the engine has been
shut off and has cooled down
completely. Since the coolant is
under pressure, you may suffer
serious burns from a spray of boil- ing hot coolant when the cap is
removed.
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.
The coolant should be changed according
to the maintenance schedule in the
“Warranty and Maintenance Booklet ”.

Black plate (345,1)
北米Model "A1130BE-A" EDITED: 2011/ 6/ 7
Drive belts1) Power steering oil pump pulley
2) Front side belt
3) Alternator pulley
4) Air conditioner compressor pulley
5) Rear side belt
6) Crank pulley
A) 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 loosen-
ess, 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 deflec-
tion 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
A 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& Checking the oil levelExcept STICheck the oil level monthly.
1. Park the vehicle on a level surface and
stop the engine.
2. Pull out the level gauge, wipe it clean,
and insert it again.
Maintenance and service
11-15
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11

Black plate (347,1)
北米Model "A1130BE-A" EDITED: 2011/ 6/ 7
Power steering fluid& Checking the fluid levelThe 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
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 power steering fluid is
being added, 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 fluidRefer to “Fluids”F 12-7.
Maintenance and service
11-17
11

Black plate (350,1)
北米Model "A1130BE-A" EDITED: 2011/ 6/ 7
11-20
Maintenance and service
Brake boosterIf 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.NOTEFor vehicles equipped with the brake
assist system, when you depress the
brake pedal strongly or suddenly, you
might feel that lighter depression of the
brake pedal generates a greater brak-
ing 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 pedalCheck 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 play1) 0.02 –0.08 in (0.5 –2.0 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.

Black plate (351,1)
北米Model "A1130BE-A" EDITED: 2011/ 6/ 7
& Checking the brake pedal
reserve distance1) 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.
Clutch pedalCheck the clutch pedal free play and
reserve distance according to the main-
tenance schedule in the “Warranty and
Maintenance Booklet ”.&Checking the clutch functionCheck 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 play1) 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.
Maintenance and service
11-21
11

Black plate (352,1)
北米Model "A1130BE-A" EDITED: 2011/ 6/ 7
11-22
Maintenance and service
Hill start assist systemEnsure 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 and clutch
pedal, with the engine running.
2. Make sure that the vehicle does not
move backward even 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 with
your SUBARU dealer.
Replacement of brake pad
and liningThe disc brakes have audible wear
indicators 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
If you continue to drive despite the
scraping noise from the audible
brake pad wear indicator, it will result in the need for costly brake
rotor repair or replacement.
&
Breaking-in of new brake
pads and liningsWhen replacing the brake pad or lining,
use only genuine SUBARU parts. After
replacement, the new parts must be
broken in 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
approximately 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

Black plate (361,1)
北米Model "A1130BE-A" EDITED: 2011/ 6/ 7
Windshield washer fluidIf you spray washer fluid on the windshield
but the supply of washer fluid appears to
diminish, check the level of washer fluid in
the tank.
Washer fluid level gaugeRemove the washer tank filler cap, then
check the fluid level indicated by the level
gauge (attached to the inside of the cap).
If the level is near the “Low”mark, add
fluid until it reaches the “Hi”level on the level gauge or the
“FULL”mark on the
tank.
Use windshield washer fluid. If windshield
washer fluid is unavailable use clean
water.
In areas where water freezes in winter,
use an anti-freeze type windshield washer
fluid. SUBARU Windshield Washer Fluid
contains 58.5% methyl alcohol and 41.5%
surfactant, by volume. Its freezing tem-
perature varies according to how much it
is diluted, as indicated in the following
table.
Washer Fluid
Concentration Freezing
Temperature
30% 10.48F( 12 8C)
50% 48F( 20 8C)
100% 498F( 45 8C)
CAUTION
Never use engine coolant as washer
fluid because it could cause paint
damage.
In order to prevent freezing of washer
fluid, check the freezing temperatures in
the table above when adjusting the fluid
concentration to the outside temperature.
If you fill the reservoir tank with a fluid with
Maintenance and service
11-31
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11