2008 TOYOTA SIENNA fuel pressure

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Tires and loading on yourTo y o t a
Underinflated or overinflated tire pressure and the
excess load may result in the deterioration of
steering ability and braking ability, leading to an
accident. Check the tire inflation pressure periodi-
cally and be sure to keep the load limits given in
this Owner ’s Manual. For details about tire inflation
pressure and load limits, see pages 446 and 523.
Leak detection pump
This pump performs fuel evaporation leakage check. This
check is done approximately five hours after the engine is
turned off. So you may hear sound coming from under the
floor around the driver ’s seat for several minutes. It does
not indicate a malfunction.
Scrapping of your Toyota
The SRS airbag and seat belt pretensioner devices in your
Toyota contain explosive chemicals. If the vehicle is
scrapped with the airbags and pretensioners left as they
are, this may cause an accident such as fire. Be sure to
have the systems of the SRS airbag and seat belt preten-
sioner removed and disposed of by the qualified service
shop or by your Toyota dealer before you dispose of your
vehicle.
Perchlorate Material
Special handling may apply,
See www.dtsc.ca.gov/hazardouswaste/perchlorate.
Your vehicle has components that may contain perchlorate.
These components may include airbag, seat belt preten-
sioners, and wireless remote control batteries.

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TESTING THE SYSTEM1. Open all the windows.
2. Set the system as described above. All the side doors and back door should
be locked with the key or wireless re-
mote control transmitter. Be sure to
wait until the indicator light starts flash-
ing.
3. Unlock any side door from the inside. The system should activate the alarm.
4. Stop the alarm as described above.
5. Repeat this operation for the other doors and hood. When testing the
hood, also check that the system is
activated when the battery terminal is
disconnected and then reconnected.
If the system does not work properly,
have it checked by your Toyota dealer.
This indicates that the fuel filler door
is on the left side of your vehicle.1. To open the fuel filler door, pull the lever up.
When refueling, turn off the engine.
CAUTION
Do not smoke, cause sparks or al-
low open flames when refueling.
The fumes are flammable.
When opening the cap, do not re-
move the cap quickly. In hot weath-
er, fuel under pressure could cause
injury by spraying out of the filler
neck if the cap is suddenly re-
moved.
Fuel tank cap

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When installing the cap, turn it clock-
wise until one click is heard, in order
to fully close it. The cap returns slight-
ly when your hand is released from the
cap after closure, however this does
not cause any problems.
If the cap is not installed securely, the
malfunction indicator lamp comes on.
Make sure the cap is tightened securely.
The indicator lamp goes off after driving
several times. If the indicator lamp does
not go off, contact your Toyota dealer as
soon as possible.
CAUTION
Make sure the cap is installed se-
curely to prevent fuel spillage in
the event of an accident.
Use only a genuine Toyota fuel tank
cap for replacement. It is designed
to regulate fuel tank pressure.
NOTICE
To prevent damage to the cap, apply
force only in the turning direction to
the cap. Do not pull or pry it.
Sliding operation
Tilting operation
To operate the moon roof, use the
switch on the overhead console.
The moon roof works when the engine
switch is in the “ON” position.
The sun shade can be opened or closed
by hand.
Sliding operation—
To open: Push the switch on the “SLIDE
OPEN” side.
The roof will fully open automatically. To
stop the roof partway, push the switch on
either the “SLIDE OPEN” or “TILT UP”
side quickly.
When you quickly push and release the
switch, the moon roof will open while the
switch is being pushed and stop when
released.
The sun shade will be opened together
with the roof.
When the moon roof is opened fully, the
deflector will raise to reduce the entering
of the strong wind. The angle of the de-
flector will be adjusted according to the
vehicle speed.
To close: Push the switch on the “TILT
UP” side.
Electric moon roof

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If the fuel tank is not empty or the fuel
tank cap is not loose...
There is a problem somewhere in the
engine, emission control system, elec-
tronic throttle control system, automatic
transmission electrical system or warn-
ing light system itself.
Contact your Toyota dealer as soon as
possible to service the vehicle.
If engine speed does not increase when
the accelerator pedal is depressed, there
may be a problem somewhere in the elec-
tronic throttle control system.
At this time, vibration may occur. Howev-
er, if you depress the accelerator pedal
more firmly and slowly, you can drive your
vehicle at low speeds. Have your vehicle
checked by your Toyota dealer as soon as
possible.
Even if the abnormality of the electronic
throttle control system is corrected during
low speed driving, the system may not be
recovered until the engine is stopped and
the engine switch is turned to “ACC” or
“LOCK” position.
CAUTION
Be especially careful to prevent erro-
neous pedal operation.
Emissions Inspection and Maintenance
(I/M) programs
Your vehicle may not pass a state
emission inspection if the malfunction
indicator lamp remains on. Contact your
Toyota dealer to check your vehicle’s
emission control system and OBD
(On −Board Diagnostics) system before
taking your vehicle for the inspection.
For details, see “Emissions Inspection and
Maintenance (I/M) programs” on page 508
in Section 6.
(f) Low Fuel Level Warning Light
This light comes on when the fuel level
in the tank becomes nearly empty. Fill up
the tank as soon as possible.
On inclines or curves, due to the move-
ment of fuel in the tank, the low fuel level
warning light may come on earlier than
usual. (g) Low Engine Oil Pressure Warning
Light
This light warns that the engine oil pres-
sure is too low.
If it flickers or stays on while you are
driving, pull off the road to a safe place
and stop the engine immediately. Call a
Toyota dealer or qualified repair shop for
assistance.
The light may occasionally flicker when
the engine is idling or it may come on
briefly after a hard stop. There is no
cause for concern if it then goes out when
the engine is accelerated slightly.
The light may come on when the oil level
is extremely low. It is not designed to
indicate low oil level, and the oil level
must be checked using the level dipstick.
NOTICE
Do not drive the vehicle with the
warning light on—even for one block.
It may ruin the engine.

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CHECKING SERVICE REMINDER
INDICATORS (except the low fuel level
warning light and low windshield
washer fluid level warning light)
1. Apply the parking brake.
2. Open one of the doors. The open door warning light should
come on.
3. Close the door. The open door warning light should go
off.
4. Turn the engine switch to “ON”, but do not start the engine.
All the service reminder indicators ex-
cept the open door warning light should
come on. The “ABS” and “VSC” warn-
ing lights, low tire pressure warning
light, dynamic laser cruise master
warning light and engine oil replace-
ment reminder light go off after a few
seconds. The SRS warning light goes
off after about 6 seconds. (“TRAC
OFF”, “READY” (dynamic laser cruise
ready mode) indicator lights and slip
indicator light also come on and go off
after a few seconds.)
If any service reminder indicator or warn-
ing buzzer does not function as described
above, have it checked by your Toyota
dealer as soon as possible.

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The tire pressure warning light may turn
on due to natural causes such as natural
air leaks or tire inflation pressure changes
caused by temperature. In this case, ad-
justing the tire inflation pressure will turn
off the light after several minutes.
Pushing the tire pressure warning reset
switch should not turn off the tire pressure
warning light. Adjusting the tire inflation
pressure will turn off the light.
The compact spare tire is not equipped
with the tire pressure warning valve and
transmitter. If a tire goes flat, the warning
light will not turn off even though the flat
tire is replaced with the spare tire. Re-
place the spare tire with the repaired tire
and adjust the proper tire inflation pressur-
e. The tire pressure warning light will turn
off after several minutes.CAUTION
Each tire, including the spare (if pro-
vided), should be checked monthly
when cold and inflated to the inflation
pressure recommended by the vehicle
manufacturer on the vehicle placard
or tire inflation pressure label (tire
and load information label). (If your
vehicle has tires of a different size
than the size indicated on the vehicle
placard or tire inflation pressure label
(tire and load information label), you
should determine the proper tire infla-
tion pressure for those tires.)
As an added safety feature, your ve-
hicle has been equipped with a tire
pressure monitoring system (TPMS–
tire pressure warning system) that il-
luminates a low tire pressure telltale
(tire pressure warning light) when one
or more of your tires is significantly
underinflated. Accordingly, when the
low tire pressure telltale (tire pres-
sure warning light) illuminates, you
should stop and check your tires as
soon as possible, and inflate them to
the proper pressure. Driving on a sig-
nificantly underinflated tire causes
the tire to overheat and can lead to
tire failure. Underinflation also re-
duces fuel efficiency and tire tread
life, and may affect the vehicle’s han-
dling and stopping ability.

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Do not leave the engine running in
an area with snow buildup, or
where it is snowing. If snowbanks
build up around the vehicle while
the engine is running, exhaust
gases may collect and enter the ve-
hicle. This may lead to death or a
serious health hazard.
When taking a nap in the vehicle,
always turn the engine off. Other-
wise, you may accidentally move
the sift lever or depress the accel-
erator pedal, which could cause an
accident or fire due to engine over-
heating. Additionally, if the vehicle
is parked in a poorly ventilated
area, exhaust gases may collect and
enter the vehicle, leading to death
or a serious health hazard.
FUNCTIONS OF ENGINE OIL
Engine oil has the primary functions of
lubricating and cooling the inside of the
engine, and plays a major role in main-
taining the engine in proper working order.
ENGINE OIL CONSUMPTION
It is normal that an engine should con-
sume some engine oil during normal
engine operation. The causes of oil
consumption in a normal engine are as
follows.
Oil is used to lubricate pistons, piston
rings and cylinders. A thin film of oil
is left on the cylinder wall when a pis-
ton moves downwards in the cylinder.
High negative pressure generated when
the vehicle is decelerating sucks some
of this oil into the combustion chamber.
This oil as well as some part of the oil
film left on the cylinder wall is burned
by the high temperature combustion
gases during the combustion process.
Oil is also used to lubricate the stems
of the intake valves. Some of this oil
is sucked into the combustion chamber
together with the intake air and is
burned along with the fuel. High tem-
perature exhaust gases also burn the
oil used to lubricate the exhaust valve
stems.The amount of engine oil consumed de-
pends on the viscosity of the oil, the
quality of the oil and the conditions the
vehicle is driven under.
More oil is consumed by high
−speed driv-
ing and frequent acceleration and decel-
eration.
A new engine consumes more oil, since
its pistons, piston rings and cylinder walls
have not become conditioned.
Oil consumption: Max. 1.0 L per 1000
km (1.1 qt./600 miles, 0.9 Imp. qt./600
miles)
When judging the amount of oil con-
sumption, note that the oil may become
diluted and make it difficult to judge
the true level accurately.
As an example, if a vehicle is used for
repeated short trips, and consumes a nor-
mal amount of oil, the dipstick may not
show any drop in the oil level at all, even
after 1000 km (600 miles) or more. This
is because the oil is gradually becoming
diluted with fuel or moisture, making it
appear that the oil level has not changed.
The diluting ingredients evaporate out
when the vehicle is then driven at high
speeds, as on an express way, making it
appear that oil is excessively consumed
after driving at high speeds.
Facts about engine oil
consumption

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IMPORTANCE OF ENGINE OIL LEVEL
CHECK
One of the most important points in prop-
er vehicle maintenance is to keep the en-
gine oil at the optimum level so that oil
function will not be impaired. Therefore, it
is essential that the oil level be checked
regularly. Toyota recommends that the oil
level be checked every time you refuel
the vehicle.
NOTICE
Failure to check the oil level regularly
could lead to serious engine trouble
due to insufficient oil.
For detailed information on oil level check,
see “Checking the engine oil level” on
page 518 in Section 7−2.
Long reach
type
Your engine is fitted with long reach
iridiumtipped spark plugs.
NOTICE
Use only Toyota genuine long reach
iridiumtipped spark plugs and do not
adjust gaps for your engine perfor-
mance and smooth driveab ility.
For details about the spark plug type, see
“Service specifications” on page 550 in
Section 8. The tandem master cylinder brake system
is a hydraulic system with two separate
sub
−systems. If either sub −system s hould
fail, the other will still work. However, the
pedal will be harder to press, and your
stopping distance will increase. Also, the
brake system warning light may come on.
CAUTION
Do not drive your vehicle with only a
single brake system. Have your
brakes fixed immediately.
BRAKE BOOSTER
The brake booster uses engine vacuum to
power −assist the brakes. If the engine
should quit while you are driving, you can
bring the vehicle to a stop with normal
pedal pressure. There is enough reserved
vacuum for one or two stops—but no
more!
Long r each iridiumtipped
spark plugs Brake system