1999 TOYOTA SIENNA engine overheat

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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NOTICE
Be careful not to overrev the en-
gine. Watch the tachometer to keep
engine rpm from going into the red
zone. The approximate maximum al-
lowable speed for each position is
given below for your reference:
”2”.................120 km/h (74 mph)
”L”..................64 km/h (40 mph)
Do not continue hill climbing or
hard towing for a long time in the
”2” or ”L” position. This may cause
severe automatic transmission dam-
age from overheating. To prevent
such damage, ”D” position should
be used in hill climbing or hard
towing.
(d) Backing up
1. Bring the vehicle to a complete stop.
2. With the brake pedal held down with
your foot, shift the selector lever to the
”R” position.
NOTICE
Never shift into reverse while the ve-
hicle is moving.
(e) Parking
1. Bring the vehicle to a complete stop.
2. With the brake pedal pressed down,
fully depress the parking brake pedal
to apply the parking brake securely.
3. With the brake pedal pressed down,
shift the selector lever to the ”P” posi-
tion.
CAUTION
While the vehicle is moving, never
attempt to move the selector lever
into ”P” position under any circum-
stances. Serious mechanical damage
and loss of vehicle control may re-
sult.
(f) Good driving practice
If the transmission is repeatedly up-
shifted and downshifted between ”D”
and overdrive when climbing a gentle
slope, the overdrive switch should be
turned off. Be sure to turn the switch
on immediately afterward.
When towing a trailer, in order to main-
tain engine braking efficiency, do not
use overdrive.
CAUTION
Always keep your foot on the brake
pedal while stopped with the engine
running. This prevents the vehicle
from creeping.
NOTICE
Do not hold the vehicle on an up-
grade with the accelerator pedal. It
can cause the transmission to over-
heat. Always use the brake pedal or
parking brake.
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The three−way 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 three−way 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 push−start or pull−start your
vehicle.
Do not turn off the ignition while
the vehicle is moving.
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 three−way catalytic
converter temperature.
If the engine becomes difficult to
start or stalls frequently, take your
vehicle in for a check−up as soon
as possible. Remember, your Toyota
dealer knows your vehicle and its
three−way catalytic converter sys-
tem best.To ensure that the three−way 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 separate ”Scheduled
Maintenance Guide” or ”Owner’s
Manual Supplement”.
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(b) Starting the engine
Before starting the engine, be sure to fol-
low the instructions in ”(a) Before crank-
ing”.
Normal starting procedure
The multiport fuel injection system/sequen-
tial multiport fuel injection system in your
engine automatically controls the proper
air−fuel mixture for starting. You can start
a cold or hot engine as follows:
1. With your foot off the accelerator ped-
al, crank the engine by turning the key
to ”START”. Release it when the en-
gine starts.
2. After the engine runs for about 10 se-
conds, you are ready to drive.
If the weather is below freezing, let the
engine warm up for a few minutes before
driving.
If the engine stalls...
Simply restart it, using the correct proce-
dure given in normal starting.
If the engine will not start...
See ”If your vehicle will not start” in Part
4.NOTICE
Do not crank for more than 30 se-
conds at a time. This may overheat
the starter and wiring systems.
Do not race a cold engine.
If the engine becomes difficult to
start or stalls frequently, have the
engine checked immediately.
Always slow down in gusty crosswinds.
This will allow you much better control.
Drive slowly onto curbs and, if pos-
sible, at a right angle. Avoid driving
onto high, sharp−edged objects and
other road hazards. Failure to do so
can lead to severe tire damage result-
ing in tire bursts.
When parking on a hill, turn the front
wheels until they touch the curb so
that the vehicle will not roll. Apply the
parking brake, and place the transmis-
sion in ”P”. If necessary, block the
wheels.
Washing your vehicle or driving through
deep water may get the brakes wet. To
see whether they are wet, check that
there is no traffic near you, and then
press the pedal lightly. If you do not
feel a normal braking force, the brakes
are probably wet. To dry them, drive
the vehicle cautiously while lightly
pressing the brake pedal with the park-
ing brake pulled. If they still do not
work safely, pull to the side of the road
and call a Toyota dealer for assistance.
Tips for driving in various
conditions
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CAUTION
Before driving off, make sure that
the parking brake is fully released
and the parking brake reminder
light is off.
Do not leave your vehicle unat-
tended while the engine is running.
Do not rest your foot on the brake
pedal while driving. It can cause
dangerous overheating, needless
wear, and poor fuel economy.
To drive down a long or steep hill,
reduce your speed and downshift.
Remember, if you ride the brakes
excessively, they may overheat and
not work properly.
Be careful when accelerating, up-
shifting, downshifting or braking on
a slippery surface. Sudden accelera-
tion or engine braking could cause
the vehicle to spin or skid.
Do not drive in excess of the speed
limit. Even if the legal speed limit
permits it, do not drive over 140
km/h (85 mph) unless your vehicle
has high−speed capability tires.
Driving over 140 km/h (85 mph) may
result in tire failure, loss of control
and possible injury. Be sure to con-
sult a tire dealer to determine
whether the tires on your vehicle
are high−speed capability tires or
not before driving at such speeds.
Do not continue normal driving
when the brakes are wet. If they are
wet, your vehicle will require a
longer stopping distance, and it
may pull to one side when the
brakes are applied. Also, the park-
ing brake will not hold the vehicle
securely.
Winter driving tips
Make sure you have a proper freeze
protection of engine coolant.
Your coolant must contain ethylene−glycol
type coolant for a proper corrosion
protection of aluminum components. Use
”Toyota Long Life Coolant” or equivalent.
See Chapter 7−2 for details about coolant
type selection.
NOTICE
Do not use alcohol type antifreeze or
plain water alone.
When it is extremely cold, we recommend
to use 60% solution for your Toyota, to
provide protection down to about −50°C
(−58°F). Do not use more than 70% solu-
tion for better coolant performance.
Check the condition of the battery and
cables.
Cold temperatures reduce the capacity of
any battery, so it must be in top shape
to provide enough power for winter start-
ing. Chapter 7−3 tells you how to visually
inspect the battery. Your Toyota dealer
and most service stations will be pleased
to check the level of charge.
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Because of the added load of the trail-
er, your vehicle’s engine may overheat
on hot days (at temperatures over
30C [85F]) when going up a long or
steep grade with a trailer. If the engine
coolant temperature gauge indicates
overheating, immediately turn off the air
conditioning (if in use), pull off the road
and stop in a safe spot. Refer to ”If
your vehicle overheats” in Part 4 of
this manual.
Always place wheel blocks under both
the vehicle and trailer wheels when
parking. Apply the parking brake firmly.
Put the transmission in ”P”. Avoid park-
ing on a slope with a trailer, but if it
cannot be avoided, do so only after
performing the following:
1. Apply the brakes and hold.
2. Have someone place wheel blocks un-
der both the vehicle and trailer wheels.
3. When the wheel blocks are in place,
release your brakes slowly until the
blocks absorb the load.
4. Apply the parking brake firmly.
5. Shift into ”P” and turn off the engine.When restarting out after parking on a
slope:
1. With the transmission in ”P” position,
start the engine. Be sure to keep the
brake pedal depressed.
2. Shift into gear.
3. Release the parking brake and brake
pedal and slowly pull or back away
from the wheel blocks. Stop and apply
your brakes.
4. Have someone retrieve the blocks.
CAUTION
Do not exceed 72 km/h (45 mph) or
the posted towing speed limit,
whichever is lower. Because insta-
bility (swaying) of a towing vehicle−
trailer combination usually in-
creases as the speed increases, ex-
ceeding 72 km/h (45 mph) may
cause loss of control.
Slow down and downshift before
descending steep or long downhill
grades. Do not make sudden down-
shifts.
Avoid holding the brake pedal down
too long or too frequently. This
could cause the brakes to overheat
and result in reduced braking effi-
ciency.
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Getting more kilometers/mileage from a
liter/gallon of fuel is easy—just take it
easy. It will help make your vehicle last
longer, too. Here are some specific tips
on how to save money on both fuel and
repairs:
Keep your tires inflated at the cor-
rect pressure. Underinflation causes
tire wear and wastes fuel. See Chapter
7−2 for instructions.
Do not carry unneeded weight in
your vehicle. Excess weight puts a
heavier load on the engine, causing
greater fuel consumption.
Avoid lengthy warm−up idling. Once
the engine is running smoothly, begin
driving—but gently. Remember, howev-
er, that on cold winter days this may
take a little longer.
Accelerate slowly and smoothly.
Avoid jackrabbit starts. Get into high
gear as quickly as possible.
Avoid long engine idling. If you have
a long wait and you are not in traffic,
it is better to turn off the engine and
start again later.
Avoid engine lug or overrevving. Use
a gear position suitable for the road on
which you are travelling.
Avoid continuous speeding up and
slowing down. Stop−and−go driving
wastes fuel.
Avoid unnecessary stopping and
braking. Maintain a steady pace. Try
to time the traffic signals so you only
need to stop as little as possible or
take advantage of through streets to
avoid traffic lights. Keep a proper dis-
tance from other vehicles to avoid sud-
den braking. This will also reduce wear
on your brakes.
Avoid heavy traffic or traffic jams
whenever possible.
Do not rest your foot on the brake
pedal. This causes needless wear,
overheating and poor fuel economy.
Maintain a moderate speed on high-
ways. The faster you drive,the greater
the fuel consumption. By reducing your
speed, you will cut down on fuel con-
sumption.
Keep the front wheels in proper
alignment. Avoid hitting the curb and
slow down on rough roads. Improper
alignment not only causes faster tire
wear but also puts an extra load on
the engine, which, in turn, wastes fuel.
Keep the bottom of your vehicle free
from mud, etc. This not only lessens
weight but also helps prevent corro-
sion.
Keep your vehicle tuned−up and in
top shape. A dirty air cleaner, improp-
er valve clearance, dirty plugs, dirty oil
and grease,brakes not adjusted, etc. all
lower engine performance and contrib-
ute to poor fuel economy. For longer
life of all parts and lower operating
costs, keep all maintenance work on
schedule, and if you often drive under
severe conditions, see that your vehicle
receives more frequent maintenance.
(For scheduled maintenance informa-
tion, please refer to the separate
”Scheduled Maintenance Guide” or
”Owner ’s Manual Supplement”).
How to save fuel and make
your vehicle last longer, too
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Part 4
IN CASE OF AN
EMERGENCY
If your vehicle will not start
If your engine stalls while
driving
If your vehicle overheats
If you have a flat tire
If your vehicle needs to be
towed
If you lose your keys
If you lose your wireless remote
control transmitter
Before making these checks, make sure
you have followed the correct starting pro-
cedure given in ”How to start the engine”
in Part 3 and that you have sufficient fuel.
If your vehicle is equipped with the engine
immobiliser system, also check whether
the other keys will start the engine. If
they work, your key may be broken. Have
the key checked at your Toyota dealer. If
none of your keys work, the system is
possibly broken. Call your Toyota dealer.
(See ”Keys (with engine immobiliser sys-
tem)” in Chapter 1−2.)
If the engine is not turning over or is
turning over too slowly—
1. Check that the battery terminals are
tight and clean.
2. If the battery terminals are O.K., switch
on the interior light.
3. If the light is out, dim or goes out
when the starter is cranked, the battery
is discharged. You may try jump start-
ing. See ”(c) Jump starting” for further
instructions.
If the light is O.K., but the engine still will
not start, it needs adjustment or repair.
Call a Toyota dealer or qualified repair
shop.NOTICE
Do not pull− or push−start the ve-
hicle. It may damage the vehicle or
cause a collision when the engine
starts. Also the three−way catalytic
converter may overheat and become a
fire hazard.
If the engine turns over at its normal
speed but will not start—
1. Check that all the push−on connectors
are tight. (For example, connectors at
the spark plugs, ignition coil and/or dis-
tributor)
2. If the connectors are O.K., the engine
may be flooded because of repeated
cranking. See ”(b) Starting a flooded
engine” for further instructions.
If your vehicle will not start—
(a) Simple checks
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