1998 TOYOTA SIENNA engine overheat

name. SIENNA (U)
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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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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 ”Owner’s
Manual Supplement/Maintenance
Schedule”.
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.
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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 ethylene−glycol an-
tifreeze in the radiator.
NOTICE
Do not use alcohol type antifreeze.
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.
Make sure the engine oil viscosity is
suitable for the cold weather.
See Chapter 7−2 for recommended viscos-
ity. Leaving a heavy summer oil in your
vehicle during winter months may cause
harder starting. If you are not sure about
which oil to use, call your Toyota deal-
er—he will be pleased to help.
Keep the door locks from freezing.
Squirt lock de−icer or glycerine into the
locks to keep them from freezing. To open
a frozen lock, try heating the key before
inserting it.
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Backing with a trailer is difficult and
requires practice. Grip the bottom of
the steering wheel and move your hand
to the left to move the trailer to the
left. Move your hand to the right to
move the trailer to the right. (This pro-
cedure is generally opposite to that
when backing without a trailer). Also,
just turn the steering wheel a little at
a time, avoiding sharp or prolonged
turning. Have someone guide you when
backing to reduce the risk of an acci-
dent.
Because stopping distance may be in-
creased, vehicle−to−vehicle distance
should be increased when towing a
trailer. For each 16 km/h (10 mph) of
speed, allow at least one vehicle and
trailer length between you and the ve-
hicle ahead. Avoid sudden braking as
you may skid, resulting in jackknifing
and loss of control. This is especially
true on wet or slippery surfaces.
Avoid jerky starts or sudden accelera-
tion.
Avoid jerky steering and sharp turns.
The trailer could hit your vehicle in a
tight turn. Slow down before making a
turn to avoid the necessity of sudden
braking.
Remember that when making a turn,
the trailer wheels will be closer than
the vehicle wheels to the inside of the
turn. Therefore, compensate for this by
making a larger than normal turning
radius with your vehicle.
Crosswinds and rough roads will ad-
versely affect handling of your vehicle
and trailer, causing sway. Pay attention
to the rear from time to time to pre-
pare yourself for being passed by large
trucks or buses, which may cause your
vehicle and trailer to sway. If swaying
happens, firmly grip the steering wheel
and reduce speed immediately but
gradually. Never increase speed. Steer
straight ahead. If you make no extreme
correction with the steering or brakes,
the vehicle and trailer will stabilize.
Be careful when passing other ve-
hicles. Passing requires considerable
distance. After passing a vehicle, do
not forget the length of your trailer and
be sure you have plenty of room be-
fore changing lanes.
In order to maintain engine braking effi-
ciency, do not use overdrive.
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.
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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.
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.
How to save fuel and make
your vehicle last longer, too
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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 con-
tribute 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 ”Own-
er ’s Manual Supplement/Maintenance
Schedule”).
CAUTION
Never turn off the engine to coast
down hills. Your power steering and
brake booster will not function with-
out the engine running. Also, the
emission control system operates
properly only when the engine is run-
ning.
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