engine SUBARU IMPREZA WRX 2014 4.G Owners Manual

Rear differential gear oil
There is no rear differential gear oil level
gauge. To check the rear differential gear
oil level, we recommend that you consult
your SUBARU dealer for inspection. &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 and rear differential
gear oil ”F 12-6. Power steering fluid &
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 isbetween “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.
Maintenance and service/Rear differential gear oil11-17
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11-20Maintenance and service/Brake booster
&Recommended clutch fluid
Refer to “Fluids ”F 12-7.
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. NOTE
For 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 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
1) 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. &
Checking the brake pedal
reserve distance
1) 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 pedal
Check the clutch pedal free play and
reserve distance according to the main-
tenance schedule in the
“Warranty 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.
Maintenance and service/Brake pedal11-21
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11-22Maintenance and service/Hill start assist system
&Checking the clutch pedal
free play
1) 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 followingcircumstances:
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 lining
The 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 isapplied.
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

11-32Maintenance and service/Replacement of wiper blades
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 followingtable.
Washer Fluid
Concentration Freezing
Temperature
30% 10.48F( 12 8C)
50% 48F( 20 8C)
100% 49 8F( 45 8C)
CAUTION
Never use engine coolant as washer
fluid because it could cause paintdamage.
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 a different concentration from the one
used previously, purge the old fluid from
the 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
temperature, it may freeze and block thenozzles.
CAUTION
. Adjust the washer fluid concen-
tration appropriately for the out-
side temperature. If the concen-
tration is inappropriate, sprayed
washer fluid may freeze on the
windshield and obstruct your
view, and the fluid may freeze in
the reservoir tank.
. State or local regulations on
volatile organic compounds may
restrict the use of methanol, a
common windshield washer anti-
freeze additive. Washer fluids
containing non-methanol anti-
freeze agents should be used
only if they provide cold weather
protection without damaging
your vehicle ’s paint, wiper blades
or washer system. Replacement of wiper blades
Grease, wax, insects, or other material on
the windshield or the wiper blade results in
jerky wiper operation and streaking on the
glass. If you cannot remove the streaks
after operating the windshield washer or if
the wiper operation is jerky, clean the
outer surface of the windshield (or rear
window) and the wiper blades using a
sponge or soft cloth with a neutral
detergent or mild-abrasive cleaner. After
cleaning, rinse the windshield and wiper
blades with clean water. The windshield is
clean if beads do not form when you rinse
the windshield with water.
CAUTION
. Do not clean the wiper blades
with gasoline or a solvent, such
as paint thinner or benzine. This
will cause deterioration of the
wiper blades.
. While removing the wiper blades
from the wiper arms, do not
return the wiper arms to the
original positions. Otherwise,
the windshield surface may bescratched.
. When returning the raised wiper
arms to the original positions,

11-38Maintenance and service/Fuses
Fuses
CAUTION
Never replace a fuse with one hav-
ing a higher rating or with material
other than a fuse because serious
damage or a fire could result.
The fuses are designed to melt during an
overload to prevent damage to the wiring
harness and electrical equipment. The
fuses are located in two fuse boxes.
One is located under the instrument panel
behind the fuse box cover on the driver ’s
seat side. To remove the cover, pull it out.
The other one (main fuse box) is housed
in the engine compartment.
The spare fuses are stored in the main
fuse box cover in the engine compart-ment.
The fuse puller is stored in the main fuse
box in the engine compartment.
1) Good
2) Blown
If any lights, accessories or other electrical
controls do not operate, inspect the

Specifications..................................................... 12-2
Dimensions ........................................................ 12-2
Engine ............................................................... 12-3
Electrical system ................................................ 12-3
Fuel ................................................................... 12-4
Lubricants. ......................................................... 12-5
Fluids ................................................................ 12-7
Engine coolant ................................................... 12-8 Tires
.................................................................. 12-9
Fuses and circuits ........................................... 12-10
Fuse panel located in the passenger compartment ................................................. 12-10
Fuse panel located in the engine compartment ................................................. 12-12
Bulb chart ......................................................... 12-14
Vehicle identification ....................................... 12-17Specifications
12

&Engine
Engine model EJ255
(2.5 L, DOHC, turbo, except STI) EJ257
(2.5 L, DOHC, turbo, STI)
Engine type Horizontally opposed, liquid cooled 4 cylinder, 4-stroke gasoline engine
Displacement cc (cu-in) 2,457 (150)
Bore 6Stroke in (mm) 3.963.1 (99.5 679.0)
Compression ratio 8.4 : 18.2 : 1
Firing order 1
– 3–2– 4
& Electrical system
Battery type and capacity (5HR) MT 12V-48AH (55D23L)
Alternator Turbo models
12V-110A
Spark plugs Turbo models
SILFR6A (NGK)
Specifications/Specifications12-3
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12-4Specifications/Specifications
&Fuel
NOTE
The engine is designed to operate using unleaded gasoline.
Model Fuel requirement Fuel tank capacity
Except STI 91 AKI (95 RON) or higher*
1
16.9 US gal (64 liters, 14.1 Imp gal)
STI 93 AKI (98 RON) or higher*2
*1: If unleaded gasoline with an octane rating of 91 AKI (95 RON) is not available, unleaded gasoline with an octane rating of 87 AKI (90 RON) or higher
may be temporarily used. For details, refer to
“Fuel ”F 7-3.
*2: If unleaded gasoline with an octane rating of 93 AKI (98 RON) is not available, unleaded gasoline with an octane rating of 91 AKI (95 RON) may be
used with no detriment to engine durability or driveability. For details, refer to “Fuel ”F 7-3.

&Lubricants
NOTE
Each quantity indicated here is only a guideline. The necessary quantity for replacement may differ slightly depending on the
temperature and other factors. ! Engine oil
For checking, adding and replacing procedure, or other details, refer to “Engine oil ”F 11-8.
Oil grade SAE viscosity No. and
applicable temperature Engine oil capacity
API (American Petroleum In-
stitute) classification SM with
the words
“ENERGY CON-
SERVING ”or SN with the
words “RESOURCE CON-
SERVING ” orILSAC (International Lubricant Specifi-
cation Advisory Committee) GF-4 or
GF-5, which can be identified with the
ILSAC certification mark (Starburst mark) 5W-30 synthetic
oil is the required oil for
optimum engine performance and pro-
tection. Conventional oil may be used if
synthetic oil is unavailable.
*: 10W-30, 10W-40, 5W-30 or 5W-40
conventional oil may be used if replen-
ishment is needed but should be changed
to 5W-30 synthetic oil at the next oil change.
· When adding the oil from L to F level:
1.1 US qt (1.0 liter, 0.9
Imp qt)
· When changing the oil and oil filter:
- Except STI:
4.4 US qt (4.2 liters, 3.7
Imp qt)
- STI:
4.5 US qt (4.3 liters, 3.8
Imp qt)
Specifications/Specifications12-5
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