2012 SUBARU IMPREZA WRX service schedule

11-14Maintenance and service
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 plugs
It 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. &
Recommended spark plugs
For the recommended spark plugs, referto “Electrical system ”F 12-3.

11-20Maintenance and service
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. &
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

range, adjust it by turning the adjusting nut
located on the parking brake lever.Parking brake stroke: 7–8 notches / 45 lbf (200 N, 20.4 kgf)
WARNING
A safe location and situation should
be selected 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
Check the parking brake stroke according
to the maintenance schedule in the“
Warranty and Maintenance Booklet ”.
When the parking brake is properly
adjusted, 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. Maintenance and service
11-23
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