2003 TOYOTA SIENNA cooling

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CAUTION
Avoid inhaling the engine exhaust.
It contains carbon monoxide, which
is a colorless and odorless gas. It
can cause unconsciousness or even
death.
Make sure the exhaust system has
no holes or loose connections. The
system should be checked from
time to time. If you hit something,
or notice a change in the sound of
the exhaust, have the system
checked immediately.
Do not run the engine in a garage
or enclosed area except for the
time needed to drive the vehicle in
or out. The exhaust gases cannot
escape, making this a particularly
dangerous situation.
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 you smell exhaust fumes in the
vehicle, drive with the windows
open and the back door and quarter
windows closed. Have the cause im-
mediately located and corrected.
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.
Engine exhaust cautionsFacts about engine oil
consumption

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5. Start your engine in the normal way.After starting, run it at about 2000 rpm
for several minutes with the accelerator
pedal lightly depressed.
6. Carefully disconnect the cables in the exact reverse order: the negative cable
and then the positive cable.
7. Carefully dispose of the battery cover cloths—they may now contain sulfuric
acid.
8. If removed, replace all the battery vent plugs.
If the cause of your battery discharging is
not apparent (for example, lights left on),
you should have it checked at your Toyota
dealer. If your engine stalls while driving...
1. Reduce your speed gradually, keeping a straight line. Move cautiously off the
road to a safe place.
2. Turn on your emergency flashers.
3. Turn the ignition key to “ACC” or “LOCK”, and try starting the engine
again.
If the engine will not start, see “If your
vehicle will not start”.
CAUTION
If the engine is not running, the pow-
er assist for the brakes and steering
will not work so steering and braking
will be much harder than usual.
If your engine coolant temperature
gauge indicates overheating, if you ex-
perience a loss of power, or if you hear
a loud knocking or pinging noise, the
engine has probably overheated. You
should follow this procedure... 1. Pull safely off the road, stop the ve- hicle and turn on your emergency
flashers. Put the transmission in “P”
and apply the parking brake. Turn off
the air conditioning if it is being used.
2. If coolant or steam is boiling out of the radiator or reservoir, stop the engine.
Wait until the steam subsides before
opening the hood. If there is no coolant
boiling over or steam, leave the engine
running and make sure the electric
cooling fan is operating. If it is not,
turn the ignition off.
CAUTION
To help avoid personal injury, keep
the hood closed until there is no
steam. Escaping steam or coolant is
a sign of very high pressure.
If your engine stalls while
driving If your vehicle overheats

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1. Engine coolant reservoir
2. Power steering fluid reservoir
3. Engine oil level dipstick
4. Engine oil filler cap
5. Brake fluid reservoir
6. Fuse blocks
7. Battery
8. Radiator
9. Electric cooling fans
10. Condenser
11. Windshield and rear window washer fluid tank
Engine compartment overview

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If you perform maintenance by yourself,
be sure to follow the correct procedure
given in this section.
You should be aware that improper or in-
complete servicing may result in operating
problems.
Performing doityourself maintenance
during the warranty period may affect your
warranty coverage. Read the separate
Toyota Warranty statement for details and
suggestions.
This section gives instructions only for
those items that are relatively easy for an
owner to perform. As explained in Section
6, there are still a number of items that
must be done by a qualified technician
with special tools.
For information on tools and Sections for
doityourself maintenance, see “Parts
and tools”.
Utmost care should be taken when work-
ing on your vehicle to prevent accidental
injury. Here are a few precautions that
you should be especially careful to ob-
serve:CAUTION
When the engine is running, keep
hands, clothing, and tools away
from the moving fan and engine
drive belts. (Removing rings,
watches, and ties is advisable.)
Right after driving, the engine
compartment—the engine, radiator,
exhaust manifold and spark plug
boots, etc.—will be hot. So be care-
ful not to touch them. Oil, fluids
and spark plugs may also be hot.
If the engine is hot, do not remove
the radiator cap or loosen the drain
plugs to prevent burning yourself.
Do not smoke, cause sparks or al-
low open flames around fuel or the
battery. Their fumes are flammable.
Do not get under your vehicle with
just the body jack supporting it. Al-
ways use automotive jack stands or
other solid supports.
Be sure that the ignition is off if
you work near the electric cooling
fans or radiator grille. With the
ignition on, the electric cooling fans
will automatically start to run if the
engine coolant temperature is high
and/or the air conditioning is on.
Use eye protection whenever you
work on or under your vehicle
where you may be exposed to flying
or falling material, fluid spray, etc.
Used engine oil contains potentially
harmful contaminants which may
cause skin disorders such as in-
flammation or skin cancer, so care
should be taken to avoid prolonged
and repeated contact with it. To re-
move used engine oil from your
skin, wash thoroughly with soap
and water.
Do not leave used oil within the
reach of children.
Dispose of used oil and filter only
in a safe and acceptable manner.
Do not dispose of used oil and fil-
ter in household trash, in sewers or
onto the ground. Call your dealer or
a service station for information
concerning recycling or disposal.
Doityourself service
precautions

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Oil identification marks
Either or both API registered marks are
added to some oil containers to help
you select the oil you should use.
The API Service Symbol is located any-
where on the outside of the container.
The top portion of the label shows the oil
quality by API (American Petroleum Insti-
tute) designations such as SL. The center
portion of the label shows the SAE viscos-
ity grade such as SAE 5W30. “Energy
Conserving” shown in the lower portion,
indicates that the oil has fuelsaving ca-
pabilities.
The ILSAC (International Lubricant Stan-
dardization and Approval Committee) Certi-
fication Mark is displayed on the front of
the container.
To ensure the best possible lubrication
performance for your engine, the “Toyota
Genuine Motor Oil” range is available,
which has been specifically tested and ap-
proved for all Toyota engines.
Please contact your Toyota dealer for fur-
ther details of the “Toyota Genuine Motor
Oil” range.Look at the seethrough coolant reser-
voir when the engine is cold. The cool-
ant level is satisfactory if it is between
the “FULL” and “LOW” lines on the
reservoir. If the level is low, add ethyl-
eneglycol type coolant for a proper
corrosion protection of aluminum com-
ponents.
The coolant level in the reservoir will vary
with engine temperature. However, if the
level is on or below the “LOW” line, add
coolant. Bring the level up to the “FULL”
line.
Always use ethyleneglycol type coolant
for a proper corrosion protection of alumi-
num components. See information in the
next column.
If the coolant level drops within a short
time after replenishing, there may be a
leak in the system. Visually check the
radiator, hoses, engine coolant filler cap,
radiator cap and drain cock and water
pump.
If you can find no leak, have your Toyota
dealer test the cap pressure and check
for leaks in the cooling system.
Checking the engine coolant
level

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CAUTION
To prevent burning yourself, do not
remove the radiator cap when the en-
gine is hot.
Coolant type selection
Use of improper coolants may damage
your engine cooling system. Your coolant
must contain ethyleneglycol type coolant
for a proper corrosion protection of your
engine that contains aluminum compo-
nents.
We have used “Toyota Genuine Long Life
Coolant” in your Toyota vehicle. In order
to avoid technical problems, we strongly
recommend using “Toyota Genuine Long
Life Coolant” or equivalent.
In addition to preventing freezing and
subsequent damage to the engine, this
type of coolant will also prevent corrosion.
Further supplemental inhibitors or additives
are neither needed nor recommended.Read the coolant container for information
on freeze protection. Follow the manufac-
turer’s directions for how much to mix
with plain water (preferably demineralized
water or distilled water). The total c
apacity
of the cooling system is given in Section
8.
We recommend to use 50% solution for
your Toyota, to provide protection down to
about 35 C (31 F). When it is extreme-
ly cold, to provide protection down to
about 50 C (58 F), 60% solution is rec-
ommended. Do not use more than 70%
solution for better coolant performance.
NOTICE
Do not use alcohol type antifreeze or
plain water alone.
The engine cooling system is integral to
maximizing performance of your Toyota
vehicle. In line with this, it is strongly
recommended that you use “Toyota
Genuine Long Life Coolant” for protecting
the system, as it is an ethyleneglycol
based premium antifreeze coolant with
excellent corrosion protection properties
that has been specifically formulated for
use in Toyota vehicles.
Please contact your Toyota dealer for fur-
ther details of the “Toyota Genuine Long
Life Coolant” range.

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Avoid sharp turns or lockedwheel
braking, as use of chains may ad-
versely affect vehicle handling.
When driving with chains installed,
be sure to drive carefully. Slow
down before entering the curves to
avoid losing control of the vehicle.
Otherwise an accident may occur.
NOTICE
Do not attempt to use a tire chain on
the compact spare tire, as it may re-
sult in damage to the vehicle as well
as the tire.
WHEN TO REPLACE YOUR WHEELS
If you have wheel damage such as
bending, cracks or heavy corrosion, the
wheel should be replaced.
If you fail to replace damaged wheels, the
tire may slip off the wheel or cause loss
of handling control.
WHEEL SELECTION
When replacing wheels, care should be
taken to ensure that the wheels are re-
placed by ones with the same load ca-
pacity, diameter, rim width, and offset.
This must be observed on compact spare
tires, too.
Correct replacement wheels are available
at your Toyota dealer.
A wheel of a different size or type may
adversely affect handling, wheel and bear-
ing life, brake cooling, speedometer/odom-
eter calibration, stopping ability, headlight
aim, bumper height, vehicle ground clear-
ance, and tire or snow chain clearance to
the body and chassis. Replacement with used wheels is not rec-
ommended as they may have been sub-
jected to rough treatment or high mileage
and could fail without warning. Also, bent
wheels which have been straightened may
have structural damage and therefore
should not be used. Never use an inner
tube in a leaking wheel which is designed
for a tubeless tire.
CAUTION
Do not use wheels other than the
manufacturer ’s recommended size, as
this may cause dangerous handling
characteristics resulting in loss of
control. Otherwise, an accident may
occur resulting in death or serious
injuries.
Initial adjustment of the tire pressure
warning system is necessary after you
have replaced your wheels. See “Tire
pressure warning system” in Section
16.
Replacing wheels

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Fuel type:Unleaded gasoline, Octane Rating 87
(Research Octane Number 91) or higher.
For improved vehicle performance, the
use of premium unleaded gasoline with
an Octane Rating of 91 (Research Oc-
tane Number 96) or higher is recom-
mended.
Fuel tank capacity, L (gal., Imp. gal.): 79 (21, 17.5) ENGINE
Valve clearance (engine cold), mm (in.):
Intake 0.15—0.25 (0.006—0.010)
Exhaust 0.25—0.35 (0.010—0.014)
Spark plug type: DENSO SK20R11
NGK IFR6A11
Spark plug gap, mm (in.): 1.1 (0.043)
Drive belt tension measured with Bor-
roughs drive belt tension gauge
No.BT3373F (used belt), Ibf: Generator belt 125 10
Power steering pump belt 115 20
ENGINE LUBRICATION
Oil capacity (drain and ref ill),
L (qt., Imp. qt.): With filter 4.7 (5.0, 4.1)
Without filter 4.5 (4.8, 4.0)
“Toyota Genuine Motor Oil” is f illed in
your Toyota vehicle. Use Toyota approved
“Toyota Genuine Motor Oil” or equivalent
to satisfy the following grade and
viscosity.
Oil grade: API grade SL “EnergyConserving” or
ILSAC multigrade engine oil Recommended oil viscosity:
SAE 5W30
Outside temperature
Please contact your Toyota dealer for fur-
ther details.
COOLING SYSTEM
Total capacity, L (qt., Imp. qt.):10.4 (11.0, 9.2)
Coolant type: “Toyota Genuine Long Life Coolant” is
filled in your Toyota vehicle. In order to
avoid technical problems, we strongly
recommend using “Toyota Genuine Long
Life Coolant” or equivalent.
Fuel Service specifications