2011 SUBARU IMPREZA WRX STI Owners Manual

Black plate (375,1)
北米Model "A1110BE-C" EDITED: 2010/ 12/ 17
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
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.
Always add genuine SUBARU coolant
and genuine SUBARU cooling system
conditioner whenever the coolant is re-
placed. Change the engine coolant and add
genuine SUBARU cooling system condi-
tioner using the following procedures
according to the maintenance schedule.
1. Remove the under cover.
2. Place a proper container under the
drain plug and loosen the drain plug.
3. Loosen the radiator cap to drain the
coolant from the radiator. Then drain the
coolant from the reserve tank. Tighten the
drain plug securely.NOTE (Turbo models only)The cap (without tabs) on top of the
radiator does not need to be removed.
To add coolant, remove the cap (with
tabs) on the coolant tank on top of the
engine.
Maintenance and service
11-15
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CONTINUED –
11

Black plate (376,1)
北米Model "A1110BE-C" EDITED: 2010/ 12/ 17
11-16
Maintenance and service
4. Install the under cover.Non-turbo models
1) Fill up to this levelTurbo models
1) Fill up to this level5. Slowly pour the coolant and fill up to just below the filler neck, allowing enough
room to add genuine SUBARU cooling
system conditioner in the radiator. Add
genuine SUBARU cooling system condi-
tioner until the coolant level reaches the
filler neck. Do not pour the coolant too
quickly, as this may lead to insufficient air
bleeding and trapped air in the system.
NOTEFor the guidelines of coolant quantity
(including coolant in the reservoir
tank), refer to
“Engine coolant ”F12-
10.1) “FULL ”level mark
2) “LOW ”level mark
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.
6. Pour the coolant and fill to the reser-
voir tank ’s “FULL ”level mark.7. Put the radiator cap back on and
tighten firmly. At this time, make sure that
the rubber gasket in the radiator cap is

Black plate (377,1)
北米Model "A1110BE-C" EDITED: 2010/ 12/ 17
correctly in place.
8. Start and race the engine at 2,000 to
3,000 rpm for 5 to 6 times within 40
seconds.
9. Stop the engine and wait until the
coolant cools down (122 to 140 8F [50 to
60 8C]). If there is any loss of coolant, add
coolant to the radiator ’s filler neck and to
the reserve tank ’s “FULL ”level.
10. Put the radiator cap and reservoir cap
back on and tighten firmly.
Air cleaner element
WARNING
Do not operate the engine with the
air cleaner element removed. The air
cleaner element not only filters
intake 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 perfo-
rated or removed, engine wear will be
excessive and engine life shortened.
It is not necessary to clean or wash the air
cleaner element.
& Replacing the air cleaner
elementReplace the air cleaner element according
to the maintenance schedule in the
“Warranty and Maintenance Booklet ”. Un-
der extremely dusty conditions, replace it
more frequently. It is recommended that
you always use genuine SUBARU parts.
! Non-turbo models1) Connector
2) Clip
3) Clamp
4) Air intake boot
5) Clip1. Unplug the connector that is attached
to the top of the air cleaner case.
2. Detach the connector cable from the
clip on the right side on the air cleaner
Maintenance and service
11-17
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11

Black plate (378,1)
北米Model "A1110BE-C" EDITED: 2010/ 12/ 17
11-18
Maintenance and service
case.
3. Loosen the screw of the clamp and
pull the air intake boot out of the air
cleaner case.
4. Unsnap the two clips holding the air
cleaner case cover.5. Open the air cleaner case and remove
the air cleaner element.
6. Clean the inside of the air cleaner case
and case cover with a damp cloth and
install a new air cleaner element.
7. To install the air cleaner case, insert
the three projections on the air cleaner
case into the slits on the air cleaner case
cover.
8. Install in the reverse order of removal. !
Turbo models
1. Use a screwdriver to undo the clips on
the air intake duct, then remove the air
intake duct.1) Connector
2) Clip

Black plate (379,1)
北米Model "A1110BE-C" EDITED: 2010/ 12/ 17
2. Unplug the connector that is attached
to the top of the air cleaner case.
3. Unsnap the two clips holding the air
cleaner case cover.4. Open the air cleaner case and remove
the air cleaner element.
5. Clean the inside of the air cleaner case
and case cover with a damp cloth and
install a new air cleaner element.
6. If the air cleaner case has been
removed, insert the three projections on
the air cleaner case into the slits on the air
cleaner case cover.
7. Install in the reverse order of removal.
Spark plugsIt may be difficult to replace the spark
plugs. It is recommended that you have
the spark plugs replaced by your
SUBARU dealer.
The spark plugs should be replaced
according to the maintenance schedule
in the “Warranty and Maintenance Book-
let ”.
CAUTION
. When disconnecting the spark
plug cables, always grasp the
spark plug cap, not the cables.
. Make sure the cables are re-
placed in the correct order.
Maintenance and service
11-19
– CONTINUED –
11

Black plate (380,1)
北米Model "A1110BE-C" EDITED: 2010/ 12/ 17
11-20
Maintenance and service
& Recommended spark plugsFor the recommended spark plugs, refer
to“Electrical system ”F 12-3.
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.

Black plate (381,1)
北米Model "A1110BE-C" EDITED: 2010/ 12/ 17
Manual transmission oil& Checking the oil levelNon-turbo models
1) Yellow handleTurbo models except STI
Check 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.1) Upper level
2) Lower level3. Pull out the level gauge again and
check the oil level on it. If it is below the
lower level, add oil through the level
gauge hole to bring the level up to the
upper level.
CAUTION
Be careful not to spill manual trans-
mission oil when adding it. If oil
touches the exhaust pipe, it may
cause a bad smell, smoke, and/or a
fire. If oil gets on the exhaust pipe,
be sure to wipe it off.NOTEThere is no transmission oil level
gauge for STI. Consult your SUBARU
dealer to check the oil level.&Recommended grade and
viscosityEach 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 ”F 12-8.
Maintenance and service
11-21
11

Black plate (382,1)
北米Model "A1110BE-C" EDITED: 2010/ 12/ 17
11-22
Maintenance and service
Automatic transmission fluid& Checking the fluid levelThe automatic transmission fluid expands
largely as its temperature rises; the fluid
level differs according to fluid temperature.
Therefore, there are two different scales
for checking the level of hot fluid and cold
fluid on the level gauge.
Though the fluid level can be checked
without warming up the fluid on the
“COLD ”range, it is recommended to
check the fluid level when the fluid is at
operating temperature.
! Checking the fluid level when the
fluid is hot
1. Drive the vehicle several miles to raise
the temperature of the transmission fluid
up to normal operating temperature; 158
to 176 8F (70 to 80 8C) is normal.
2. Park the vehicle on a level surface and
set the parking brake.
3. First shift the select lever in each
position. Then shift it in the “P”position,
and run the engine at idling speed.
1) Yellow handle1) HOT range
2) COLD range
3) Upper level
4) Lower level4. Pull out the level gauge and check the fluid level on the gauge. If it is below the
lower level on the
“HOT”range, add the
recommended automatic transmission
fluid up to the upper level.
! Checking the fluid level when the
fluid is cold
When the fluid level has to be checked
without time to warm up the automatic
transmission, check to see that the fluid
level is between the lower level and upper
level on the “COLD”range. If it is below
that range, add fluid up to the upper level.
Be careful not to overfill.
CAUTION
Be careful not to spill automatic
transmission fluid when adding it.
If automatic transmission fluid
touches the exhaust pipe, it may
cause a bad smell, smoke, and/or a
fire. If automatic transmission fluid
gets on the exhaust pipe, be sure to
wipe it off.