2006 SUBARU IMPREZA fuel pressure

Maintenance and service 11-31
– CONTINUED –
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
outside temperature. It is best to check tire
pressure outdoors before driving the vehi-
cle.
When a tire becomes warm, the air inside
it expands, causing the tire pressure to in-
crease. Be careful not to mistakenly re-
lease air from a warm tire to reduce its
pressure.
NOTE
The air pressure in a tire increases
by approximately 4.3 psi (30 kPa, 0.3
kgf/cm
2) when the tire becomes warm.
The tires are considered cold when
the vehicle has been parked for at least
three hours or has been driven less
than one mile (1.6 km).
Incorrect tire pressures detract from con-
trollability and ride comfort, and they
cause the tires to wear abnormally.
Correct tire pressure (tread worn
evenly)
Roadholding is good, and steering is re-
sponsive. Rolling resistance is low, so fuel
consumption is also lower.
B00164Do not let air out of warm tires to ad-
just pressure. Doing so will result in
low tire pressure.
B00050

11-32 Maintenance and service
Abnormally low tire pressure (tread
worn at shoulders)
Rolling resistance is high, so fuel con-
sumption is also higher.Abnormally high tire pressure (tread
worn in center)
Ride comfort is poor. Also, the tire magni-
fies the effects of road-surface bumps and
dips, possibly resulting in vehicle damage.
If the tire placard shows tire pressures for
the vehicle when fully loaded and for the
vehicle when towing a trailer, adjust the
tire pressures to the values that match
current loading conditions.
Wheel balance
Each wheel was correctly balanced when
your vehicle was new, but the wheels will
become unbalanced as the tires become
worn during use. Wheel imbalance caus-
es the steering wheel to vibrate slightly at
certain vehicle speeds and detracts from
the vehicle ’s straight-line stability. It can
also cause steering and suspension sys-
tem problems and abnormal tire wear. If
you suspect that the wheels are not cor-
rectly balanced, have them checked and
adjusted by your SUBARU dealer. Also
have them adjusted after tire repairs and
after tire rotation.
NOTE
Loss of correct wheel alignment* caus-
es the tires to wear on one side and re-
duces the vehicle ’s running stability.
B00051B00052
Driving at high speeds with exces-
sively low tire pressures can cause
the tires to deform severely and to
rapidly become hot. A sharp in-
crease in temperature could cause
tread separation, and destruction of
the tires. The resulting loss of vehi-
cle control could lead to an acci-
dent.

12-4 Specifications
Capacities
AT: Automatic transmission
MT: Manual transmission
Tires
Fuel tank15.9 US gal (60 liters, 13.2 Imp gal)
Engine oil4.2 US qt (4.0 liters, 3.5 Imp qt)
Transmission oil (MT)5-speed3.7 US qt (3.5 liters, 3.1 Imp qt)
6-speed4.3 US qt (4.1 liters, 3.6 Imp qt)
AT differential gear oil1.3 US qt (1.2 liters, 1.1 Imp qt)
Rear differential gear oilWRX-STI1.1 US qt (1.0 liters, 0.9 Imp qt)
Others0.8 US qt (0.8 liters, 0.7 Imp qt)
Transmission oil (AT)10.0 US qt (9.5 liters, 8.4 Imp qt)
Power steering fluid0.7 US qt (0.7 liter, 0.6 Imp qt)
Engine coolantNon-turbo engineMT7.4 US qt (7.0 liters, 6.2 Imp qt)
AT7.3 US qt (6.9 liters, 6.1 Imp qt)
Turbo engineMT8.1 US qt (7.7 liters, 6.8 Imp qt)
Item2.5i, OUTBACK SPORTWRXWRX-STI
Tire sizeP205/55R16 89V215/45R17 91W225/45R17 90W
Wheel size16  6 1
/2 JJ17
 7 JJ17  8 JJ
PressureFront33 psi (230 kPa, 2.3 kgf/cm 2
)33 psi (230 kPa, 2.3 kgf/cm 2
)36 psi (250 kPa, 2.5 kgf/cm 2
)
Rear30 psi (210 kPa, 2.1 kgf/cm 2
)32 psi (220 kPa, 2.2 kgf/cm 2
)30 psi (210 kPa, 2.1 kgf/cm 2
)
Temporary spare tireSizeT135/70 D16T135/70 D17
Pressure60 psi (420 kPa, 4.2 kgf/cm 2
)

12-10 Specifications
Vehicle identification
1 2
3
4
5
6
7 9
8
C00108
1) Vehicle identification number
2) Vacuum hose connections label/
Emission control label
3) Tire inflation pressure label
4) Certification plate
5) Bar cord label (U.S. only)
6) Vehicle identification number plate
7) Model number plate
8) Radio noise label (Canada only)
9) Fuel label

Consumer information and Reporting safety defects 13-7
– CONTINUED –
asymmetrical tire that has a particu-
lar side that must always face out-
ward when mounting on a vehicle.
Accessory weight
The combined weight (in excess of
those standard items which may be
replaced) of floor mats, leather seats
and cross bars to the extent that these
items are available as factory-in-
stalled equipment (whether installed
or not).
Curb weight
The weight of a motor vehicle with
standard equipment including the
maximum capacity of fuel, oil, and
coolant and air conditioning.
Maximum loaded vehicle weight
The sum of curb weight, accessory
weight, vehicle capacity weight and
production options weight.
Normal occupant weight
150 lbs (68 kg) times the number of
occupants (3 occupants).
Occupant distribution
Distribution of occupants in a vehicle,
2 in front, 1 in rear seat.
Production options weight
The combined weight of those in-
stalled regular production options weighing over 5.1 lbs (2.3 kg) in ex-
cess of those standards items which
they replace, not previously consid-
ered in curb weight or accessory
weight.
Vehicle capacity weight
The total weight of cargo, luggage
and occupants that can be added to
the vehicle.
Vehicle maximum load on a tire
Load on an individual tire that is deter-
mined by distributing to each axle its
share of the maximum loaded vehicle
weight and dividing by two.
Vehicle normal load on a tire
Load on an individual tire that is deter-
mined by distributing to each axle its
share of the curb weight, accessory
weight, and normal occupant weight
and dividing by two.
Tire care – maintenance and
safety practices
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.
Inspect the tire tread regularly and
replace the tires before their tread wear indicators become visible. When
a tire
’s tread wear indicator becomes
visible, the tire is worn beyond the ac-
ceptable limit and must be replaced
immediately. With a tire in this condi-
tion, driving at even low speeds in wet
weather can cause the vehicle to hy-
droplane. Possible resulting loss of
vehicle control can lead to an acci-
dent.
To maximize the life of each tire and
ensure that the tires wear uniformly, it
is best to rotate the tires every 7,500
miles (12,500 km). Rotating the tires
involves switching the front and rear
tires on the right-hand side of the ve-
hicle and similarly switching the front
and rear tires on the left-hand side of
the vehicle. (Each tire must be kept on
its original side of the vehicle.) Re-
place any damaged or unevenly worn
tire at the time of rotation. After tire ro-
tation, adjust the tire pressures and
make sure the wheel nuts are correct-
ly tightened. A tightening torque spec-
ification and a tightening sequence
specification for the wheel nuts can be
found “Flat tires ” section in chapter 9.

GAS STATION REFERENCE
Fuel:
2.5-liter non-turbo models
Use only unleaded gasoline with an octane rating of 87 AKI or
higher.
WRX
Use premium unleaded gasoline with an octane rating of 91 AKI or
higher. If premium unleaded gasoline with an octane r ating of 91
AKI is not available, regular unleaded gasoline with octane rating
of 87 AKI or higher may be temporarily used. For opti mum engine
performance and driveability, it is required that you use premium
grade unleaded gasoline with an octane rating of 91 AKI or higher.
WRX-STI
Use super-premium unleaded gasoline with an octane rat ing of 93
AKI or higher. If super-premium unleaded gasoline wi th an octane
rating of 93 AKI is not available, premium unleaded g asoline with
octane rating of 91 AKI or higher may be temporarily u sed. For op-
timum engine performance and driveability, it is requir ed that you
use super-premium grade unleaded gasoline with an oct ane ratingof 93 AKI or higher.
Fuel octane rating
This octane rating is the average of the Research Octane
and Mo-
tor Octane numbers and is commonly referred to as the An ti Knock
Index (AKI). Refer to “Fuel ” section in this manual.
Fuel capacity:
15.9 US gal (60 liters, 13.2 Imp gal)
Engine oil:
Use only API classification SM with the words “ENERGY CON-
SERVING ” and the ILSAC certification mark (starburst mark) dis-
played on the container.
Engine oil capacity:
4.2 US qt (4.0 liters, 3.5 Imp qt)
Cold tire pressure:
Item 2.5i, OUTBACK SPORT WRX WRX-STI
Tire size P205/55R16 89V 215/45R17 91W 225/45R17 90W
Wheel size 16  6 1
/2 JJ 17
 7 JJ 17  8 JJ
Pressure Front 33 psi (230 kPa, 2.3 kgf/cm 2
) 33 psi (230 kPa, 2.3 kgf/cm 2
) 36 psi (250 kPa, 2.5 kgf/cm 2
)
Rear 30 psi (210 kPa, 2.1 kgf/cm 2
) 32 psi (220 kPa, 2.2 kgf/cm 2
) 30 psi (210 kPa, 2.1 kgf/cm 2
)
Temporary spare
tire Size
T135/70 D16 T135/70 D17
Pressure 60 psi (420 kPa, 4.2 kgf/cm2
)