TOYOTA SIENNA 2008 XL20 / 2.G Owners Manual

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The threeway catalytic converter is an
emission control device installed in the
exhaust system.
The purpose is to reduce pollutants in the
exhaust gas.
CAUTION
Keep people and combustible mate-
rials away from the exhaust pipe
while the engine is running. The
exhaust gas is very hot.
Do not drive, idle or park your ve-
hicle over anything that might burn
easily such as grass, leaves, paper
or rags.
NOTICE
A large amount of unburned gases
flowing into the threeway catalytic
converter may cause it to overheat
and create a fire hazard. To prevent
this and other damage, observe the
following precautions:
Use only unleaded gasoline.
 Do not drive with an extremely low
fuel level; running out of fuel could
cause the engine to misfire, creat-
ing an excessive load on the three
way catalytic converter.
 Do not allow the engine to run at
idle speed for more than 20 min-
utes.
 Avoid racing the engine.
 Do not pushstart or pullstart your
vehicle.
 Do not turn off the engine switch
while the vehicle is moving.
Threeway catalytic converters

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Keep your engine in good running
order. Malfunctions in the engine
electrical system, electronic ignition
system/distributor ignition system
or fuel system could cause an ex-
tremely high threeway catalytic
converter temperature.
 If the engine becomes difficult to
start or stalls frequently, take your
vehicle in for a checkup as soon
as possible. Remember, your Toyota
dealer knows your vehicle and its
threeway catalytic converter sys-
tem best.
 To ensure that the threeway cata-
lytic converter and the entire emis-
sion control system operate proper-
ly, your vehicle must receive the
periodic inspections required by the
Toyota Maintenance Schedule. For
scheduled maintenance information,
refer to the “Scheduled Maintenance
Guide” or “Owner ’s Manual Supple-
ment”.CAUTION
Exhaust gases include harmful car-
bon monoxide (CO) that is colorless
and odorless. Inhaling exhaust
gases may lead to death or a seri-
ous health hazard.
The exhaust should be checked
occasionally. If there is a hole or
crack caused by corrosion, damage
to a joint or abnormal exhaust
noise, be sure to have the vehicle
inspected and repaired by your
Toyota dealer. Failure to do so may
allow exhaust gases to enter the
vehicle, resulting in death or a
serious health hazard.
If the vehicle is in a poorly venti-
lated area, turn the engine off. In
a closed area, such as a garage,
exhaust gases may collect and en-
ter the vehicle. This may lead to
death or a serious health hazard.
Do not remain for a long time in a
parked vehicle with the engine run-
ning. If it is unavoidable, however,
do so only in an unconfined area
and adjust the heating or cooling
system to force outside air into the
vehicle.
Keep the back door and quarter
windows closed while driving. An
open or unsealed back door and
quarter windows may cause exhaust
gases to be drawn into the vehicle.
To allow proper operation of your
vehicle’s ventilation system, keep
the inlet grilles in front of the wind-
shield clear of snow, leaves, or oth-
er obstructions.
If the smell of exhaust is noticed
inside the vehicle, open the win-
dows. Large amounts of exhaust in
the vehicle can cause driver drowsi-
ness and an accident, resulting in
death or a serious health hazard.
Have the vehicle inspected by your
Toyota dealer immediately.
Engine exhaust cautions

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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

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CAUTION
Do not pump the brake pedal if the
engine stalls. Each push on the
pedal uses up your reserved vacu-
um.
Even if the power assist is com-
pletely lost, the brakes will still
work. But you will have to push the
pedal hard, much harder than nor-
mal. And your braking distance will
increase.
ANTILOCK BRAKE SYSTEM (with
“ABS” warning light)
The antilock brake system is designed
to help prevent lockup of the wheels
during a sudden braking or braking on
slippery road surfaces. This assists in
providing directional stability and steer-
ing performance of the vehicle under
these circumstances.
Effective way to press the ABS brake
pedal: When the anti −lock brake system
function is in action, you may feel the
brake pedal pulsating and hear a noise.
In this situation, to let the anti −lock
brake system work for you, just hold the
brake pedal down more firmly. Do not
pump the brake in a panic stop. This
will result in reduced braking performan-
ce.
The anti −lock brake system becomes op-
erative after the vehicle has accelerated
to a speed in excess of approximately 10
km/h (6 mph). It stops operating when the
vehicle decelerates to a speed below
approximately 5 km/h (3 mph).
Depressing the brake pedal on slippery
road surfaces such as on a manhole cov-
er, a steel plate at a construction site,
joints in a bridge, etc. on a rainy day
tends to activate the anti −lock brake sys-
tem.
You may hear a click or motor sound in
the engine compartment for a few seconds
when the engine is started or just after
the vehicle begins to move. This means
that the anti −lock brake system is in the
self −check mode, and does not indicate a
malfunction. When the antilock brake system is ac-
tivated, the following conditions may
occur. They do not indicate a malfunc-
tion of the system:
You may hear the anti
−lock brake sys-
tem operating and feel the brake pedal
pulsating and the vibrations of the ve-
hicle body and steering wheel. You
may also hear the motor sound in the
engine compartment even after the ve-
hicle is stopped.
At the end of the anti −lock brake sys-
tem activation, the brake pedal may
move a little forward.

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CAUTION
Do not overestimate the antilock
brake system: Although the antilock
brake system assists in providing ve-
hicle control, it is still important to
drive with all due care and maintain
a moderate speed and safe distance
from the vehicle in front of you, be-
cause there are limits to the vehicle
stability and effectiveness of steering
wheel operation even with the anti
lock brake system on.
If tires grip performance exceeds its
capability, or if hydroplaning occurs
during high speed driving in the rain,
the antilock brake system does not
provide vehicle control.
Antilock brake system is not de-
signed to shorten the stopping dis-
tance: Always drive at the moderate
speed and maintain a safe distance
from the vehicle in front of you.
Compared with vehicles without an
antilock brake system, your vehicle
may require a longer stopping dis-
tance in the following cases:
Driving on rough, gravel or snow
covered roads.
Driving with tire chains installed.
Driving over the steps such as the
joints on the road.
Driving on roads where the road
surface is pitted or has other differ-
ences in surface height.
Install all 4 tires of specified size at
appropriate pressure: The antilock
brake system detects vehicle speeds
using the speed sensors for respec-
tive wheels’ turning speeds. The use
of tires other than specified may fail
to detect the accurate turning speed
resulting in a longer stopping dis-
tance.
Ty p e A
Ty p e B

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“ABS” warning light
Vehicles without the vehicle stability
control system—
The light comes on when the engine
switch is turned to the “ON” position. If
the anti−lock brake system works properly,
the light turns off after a few seconds.
Thereafter, if either of the systems mal-
functions, the light comes on again.
When the “ABS” warning light is on (and
the brake system warning light is off), the
anti −lock brake system does not operate,
but the brake system still operates con-
ventionally.
When the “ABS” warning light is on (and
the brake system warning light is off), the
anti −lock brake system does not operate
but the brake assist system still operates.
In this case the wheels could lock up
during a sudden braking or braking on
slippery road surfaces. If either of the following conditions
occurs, this indicates a malfunction
somewhere in the components moni-
tored by the warning light system. Con-
tact your Toyota dealer as soon as
possible to service the vehicle.
The light does not come on when the
engine switch is turned to the “ON”
position, or remains on.
The light comes on while you are driv-
ing.
A warning light turning on briefly during
operation does not indicate a problem.
CAUTION
If the “ABS” warning light remains on
together with the brake system warn-
ing light, immediately stop your ve-
hicle at a safe place and contact your
Toyota dealer.
In this case, not only the antilock
brake system will fail but also the
vehicle will become extremely unsta-
ble during braking.
Vehicles with the vehicle stability con-
trol system—
The light comes on when the engine
switch is turned to the “ON” position. If
the anti −lock brake system and the brake
assist system work properly, the light
turns off after a few seconds. Thereafter,
if either of the systems malfunctions, the
light comes on again.
When the “ABS” warning light is on (and
the brake system warning light is off), the
anti −lock brake system, the brake assist
system, the traction control system and
the vehicle stability control system do not
operate, but the brake system still oper-
ates conventionally.
When the “ABS” warning light is on (and
the brake system warning light is off), the
anti −lock brake system does not operate
so that the wheels could lock up during
a sudden braking or braking on slippery
road surfaces.
If either of the following conditions
occurs, this indicates a malfunction
somewhere in the components moni-
tored by the warning light system. Con-
tact your Toyota dealer as soon as
possible to service the vehicle.

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The light does not come on when the
engine switch is turned to the “ON”
position, or remains on.
The light comes on while you are driv-
ing.
A warning light turning on briefly during
operation does not indicate a problem.
CAUTION
If the “ABS” warning light remains on
together with the brake system warn-
ing light, immediately stop your ve-
hicle at a safe place and contact your
Toyota dealer.
In this case, not only the antilock
brake system will fail but also the
vehicle will become extremely unsta-
ble during braking.
DRUMINDISC TYPE PARKING BRAKE
SYSTEM (with rear disc brake)
Your vehicle has a drum −in −disc type
parking brake system. This type of brake
system n eeds bedding −down of the brake
shoes periodically or whenever the parking
brake shoes and/or drums are replaced.
Have your Toyota dealer perform the bed-
ding− down. BRAKE ASSIST SYSTEM
When you slam the brakes on, the
brake assist system judges as an emer-
gency stop and provides more powerful
braking for a driver who cannot hold
down the brake pedal firmly.
When you slam the brakes on, more pow-
erful braking will be applied. At this time,
you may hear a sound in the engine
compartment and feel the vibrations of the
brake pedal. This does not indicate a mal-
function.
Vehicles with the vehicle stability control
system—
The brake assist system becomes opera-
tive after the vehicle has accelerated to
a speed in excess of approximately 10
km/h (6 mph). It stops operating when the
vehicle decelerates to a speed below
approximately 5 km/h (3 mph).
For an explanation of this system’s warn-
ing light, see “Service reminder indicators
and warning buzzers” on page 191 in Sec-
tion 1
−6.
The brake pad wear limit indicators on
your disc brakes give a warning noise
when the brake pads are worn to where
replacement is required.
If you hear a squealing or scraping noise
while driving, have the brake pads
checked and replaced by your Toyota
dealer as soon as possible. Expensive ro-
tor damage can result if the pads are not
replaced when necessary.
Brake pad wear limit
indicators

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The vehicle identification number (VIN)
is the legal identifier for your vehicle.
This number is on the left top of the
instrument panel, and can be seen
through the windshield from outside.
This is the primary identification number
for your Toyota. It is used in registering
the ownership of your vehicle.The vehicle identification number (VIN) is
also on the Certification Label.The engine number is stamped on the
engine block as shown.
Your Toyota’s identification—
—Vehicle identification
number—Engine number

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Your new vehicle carries theft preven-
tion labels which are approximately 47
mm (1.90 in.) by 12 mm (0.50 in.).
The purpose of these labels is to reduce
the incidence of vehicle thefts by facilitat-
ing the tracing and recovery of parts from
stolen vehicles. The label is designed so
that once it is applied to a surface, any
attempt to remove it will result in destroy-
ing the integrity of the label. Transferring
these labels intact from one part to anoth-
er, will be impossible.
NOTICE
You should not attempt to remove the
theft prevention labels as it may vio-
late certain state or federal laws.
CAUTION
Do not modify the suspension/chassis
with lift kits, spacers, springs, etc. It
can cause dangerous handling charac-
teristics, resulting in loss of control.
Theft prevention labels
(except for Canada)Suspension and chassis