1999 TOYOTA SIENNA cooling

name. SIENNA (45403U)
11 6
With tachometer
Without tachometer
The gauge indicates the engine coolant
temperature when the ignition switch is
on. The engine operating temperature
will vary with changes in weather and
engine load.
If the needle moves into the red zone,
your engine is too hot. If your vehicle
overheats, stop your vehicle and allow the
engine to cool.
Your vehicle may overheat during severe
operating conditions, such as:
Driving up a long hill on a hot day.
Reducing speed or stopping after high
speed driving.
Idling for a long period with the air
conditioning on in stop−and−go traffic.
Towing a trailer.
NOTICE
Do not remove the thermostat in
the engine cooling system as this
may cause the engine to overheat.
The thermostat is designed to con-
trol the flow of coolant to keep the
temperature of the engine within
the specified operating range.
Do not continue driving with an
overheated engine. See ”If your ve-
hicle overheats” in Part 4.
Engine coolant temperature
gauge
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Heating
For best results, set controls to:
Fan speed—Any setting except ”OFF”
Temperature—To w a r d s WARM
(red zone)
Air intake—FRESH (outside air)
Air flow—FLOOR
Air conditioning—OFF
For quick heating, select recirculated
air for a few minutes. To keep the
windows from fogging, select fresh af-
ter the vehicle interior has been
warmed.
Press the ”A/C” button on for dehumidi-
fied heating.
Choose floor/windshield air flow to heat
the vehicle interior while defrosting or
defogging the windshield.Air conditioning
For best results, set controls to:
Fan speed—Any setting except ”OFF”
Temperature—To w a r d s COLD
(blue zone)
Air intake—FRESH (outside air)
Air flow—PANEL
Air conditioning—ON
For quick cooling, move the air intake
selector to recirculate for a few min-
utes.
Ventilation
For best results, set controls to:
Fan speed—Any setting except ”OFF”
Temperature—To w a r d s COLD
(blue zone)
Air intake—FRESH (outside air)
Air flow—PANEL
Air conditioning—OFF
Defogging
The inside of the windshield
For best results, set controls to:
Fan speed—Any setting except ”OFF”
Temperature—To w a r d s WARM
(red zone) to heat;
COLD (blue zone) to
cool
Air intake—FRESH (outside air)
Air flow—WINDSHIELD
Turning the air flow control knob to wind-
shield position turns on the defroster−
linked air conditioning. This is to clean up
the front view more quickly.
When the ”A/C” button is not pressed in,
turning the air flow control knob to anoth-
er position turns off the air conditioning.
On humid days, do not blow cold air
on the windshield—the difference be-
tween the outside and inside tempera-
tures could make the fogging worse.
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Engine exhaust cautions
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.
Facts about engine oil
consumption
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If your vehicle overheats
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.
3. Look for obvious coolant leaks from the
radiator, hoses, and under the vehicle.
However, note that water draining from
the air conditioning is normal if it has
been used.
CAUTION
When the engine is running, keep
hands and clothing away from the
moving fan and engine drive belts.
4. If the coolant is leaking, stop the en-
gine immediately. Call a Toyota dealer
for assistance.
5. If there are no obvious leaks, check
the coolant reservoir. If it is dry, add
coolant to the reservoir while the en-
gine is running. Fill it about half full.
CAUTION
Do not attempt to remove the radiator
cap when the engine and radiator are
hot. Serious injury could result from
scalding hot fluid and steam blown
out under pressure.
6. After the engine coolant temperature
has cooled to normal, again check the
coolant level in the reservoir. If neces-
sary, bring it up to half full again. Seri-
ous coolant loss indicates a leak in the
system. You should have it checked as
soon as possible at your Toyota dealer.
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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. Electric cooling fans
9. Windshield and rear window washer
fluid tank
Engine compartment overview
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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.
NOTICE
Remember that battery and ignition
cables carry high currents or volt-
ages. Be careful of accidentally
causing a short circuit.
Add only demineralized or distilled
water to fill the radiator. And if you
spill some of the coolant, be sure
to wash off with water to prevent it
from damaging the parts or paint.
Do not allow dirt or anything else
to fall through the spark plug holes.
Do not pry the outer electrode of a
spark plug against the center elec-
trode.
Use only spark plugs of the speci-
fied type. Using other types will
cause engine damage, loss of per-
formance or radio noise.
Do not reuse platinum−tipped spark
plugs by cleaning or regapping.
Do not overfill automatic transmis-
sion fluid, or the transmission
could be damaged.
Do not drive with the air cleaner
filter removed, or excessive engine
wear could result. Also backfiring
could cause a fire in the engine
compartment.
Be careful not to scratch the glass
surface with the wiper frame.
When closing the engine hood,
check to see that you have not for-
gotten any tools, rags, etc.
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Look at the see−through 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-
ene−glycol 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 ethylene−glycol 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.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 ethylene−glycol type coolant
for a proper corrosion protection of your
engine that contains aluminum
components. Use ”Toyota 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 capacity
of the cooling system is given in Part 8.We recommend to use 50% solution for
your Toyota, to provide protection down to
about −35C (−31F). 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.
Checking the engine coolant
level
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Replacing wheels
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 they may
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.
Aluminum wheel precautions
After driving your vehicle the first 1600
km (1000 miles), check that the wheel
nuts are tight.
If you have rotated, repaired, or
changed your tires, check that the
wheel nuts are still tight after driving
1600 km (1000 miles).
When using tire chains, be careful not
to damage the aluminum wheels.
Use only the Toyota wheel nuts and
wrench designed for your aluminum
wheels.
When balancing your wheels, use only
Toyota balance weights or equivalent
and a plastic or rubber hammer.
As with any wheel, periodically check
your aluminum wheels for damage. If
damaged, replace immediately.
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