2008 TOYOTA SIENNA engine overheat

08 SIENNA_U (L/O 0801)
107
2008 SIENNA from Aug. ’08 Prod. (OM45455U)
To use the armrest, pull it down as shown
above.
NOTICE
To prevent damage to the armrest,
avoid putting heavy loads on it.
To turn on the seat heater, move the
dial upward (“L” dial for the left front
seat or “R” dial for the right front
seat). At this time, the indicator light
will illuminate to indicate the seat heat-
er is operating.
Move the dial upward or downward to ad-
just to the desired temperature.
To turn it off, move the dial downward
until it stops.
When the seat heater is not in use, move
the dial fully downward.
The engine switch must be in the “ON”
position to operate seat heaters.
CAUTION
Occupants must use caution when op-
erating the seat heater because it
may make them feel too hot or cause
burns at low temperatures (erythema,
varicella). Use extra caution for;
Babies, small children, elderly per-
sons, sick persons or persons with
physical disabilities
Persons who have sensitive skin
Persons who are exhausted
Persons who have taken alcohol or
drugs which induce sleep (sleeping
drug, cold remedy, etc.)
To prevent the seat from overheating,
do not use the seat heater with a
blanket, cushion, or other insulating
objects which cover the seat.
Armrests Seat heaters

08 SIENNA_U (L/O 0801)
189
2008 SIENNA from Aug. ’08 Prod. (OM45455U)
The gauge indicates the engine coolant
temperature when the engine 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” on page 470 in
Section 4.
The tachometer indicates engine speed
in thousands of rpm (revolutions per
minute). Use it while driving to select
correct shift points and to prevent en-
gine lugging and overrevving.
Driving with the engine running too fast
causes excessive engine wear and poor
fuel economy. Remember, in most cases
the slower the engine speed, the greater
the fuel economy.
NOTICE
Do not let the indicator needle get
into the red zone. This may cause
severe engine damage.
Tachometer

08 SIENNA_U (L/O 0801)
207
2008 SIENNA from Aug. ’08 Prod. (OM45455U)
Vehicles with cruise control or dynamic
laser cruise control—When the cruise con-
trol is being used, even if you downshift
from “D” to “4”, engine braking will not be
enabled because the cruise control is not
cancelled.
For ways to decrease the vehicle speed,
see “Cruise control” on page 222 or “Dy-
namic laser cruise control” on page 225
in this Section.
CAUTION
Be careful when downshifting on a
slippery surface. Abrupt shifting
could cause the vehicle to skid or
spin.
(d) Using “3”, “2” and “L” positions
The “3”, “2” and “L” positions are used for
strong engine braking as described pre-
viously.
With the selector lever in “3”, “2” or “L”,
you can start the vehicle in motion as
with the lever in “D”.
With the selector lever in “3” or “2”, the
vehicle will start in first gear and automat-
ically shift to third gear or second gear.With the selector lever in “L”, the trans-
mission is engaged in first gear.
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:
Twowheel drive models “3” 162 km/h (100 mph) . . . . . . . .
“2” 104 km/h (64 mph) . . . . . . . .
“L” 58 km/h (36 mph) . . . . . . . . .
Allwheel drive models “3” 154 km/h (95 mph) . . . . . . . . .
“2” 99 km/h (61 mph) . . . . . . . . . .
“L” 55 km/h (34 mph) . . . . . . . . . .
 Do not continue hill climbing or
hard towing for a long time in the
“3”, “2” or “L” position. This may
cause severe automatic transmis-
sion damage from overheating. To
prevent such damage, “4” position
should be used in hill climbing or
hard towing.

08 SIENNA_U (L/O 0801)
208
2008 SIENNA from Aug. ’08 Prod. (OM45455U)
(e) Backing up1. 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.
Vehicles with rear view monitor system—
When the selector lever is shifted into “R”
position with the engine switch in the
“ON” position, rear view monitor system
will activate. For instructions, see “Rear
view monitor system” on page 393 in Sec-
tion 1 −10.
(f) 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
Never attempt to move the selector
lever into “P” position under any cir-
cumstances while the vehicle is mov-
ing. Serious mechanical damage and
loss of vehicle control may result.
(g) Good driving practice
If the transmission repeatedly shifts up
and down between fourth gear and
overdrive when climbing a gentle slope,
shift the selector lever to the “4” posi-
tion. Be sure to shift the selector lever
to the “D” position immediately after-
ward.
When towing a trailer, in order to main-
tain engine braking efficiency, do not
use “D” position.
CAUTION
Always keep your foot on the brake
pedal while stopped with the engine
running. This prevents the vehicle
from creeping.
NOTICE
Always use the brake pedal or the
parking brake to hold the vehicle on
an upgrade. Do not attempt to hold
the vehicle using the accelerator ped-
al, as this can cause the transmission
to overheat.
(h) If you cannot shift the selector le- ver out of “P” position
If you cannot shift the selector lever from
the “P” position even though the brake
pedal is depressed, use the shift lock
override button. For instructions, see “If
you cannot shift automatic transmission
selector lever” on page 493 in Section 4.

08 SIENNA_U (L/O 0801)
423
2008 SIENNA from Aug. ’08 Prod. (OM45455U)
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

08 SIENNA_U (L/O 0801)
454
2008 SIENNA from Aug. ’08 Prod. (OM45455U)
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 skid or spin.
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 highspeed 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 highspeed 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.
Driving on a slippery road surface
Drive carefully when it is raining, because
visibility will be reduced, the windows may
become fogged−up, and the road will be
slippery.
Drive carefully when it starts to rain,
because the road surface will be espe-
cially slippery.
Refrain from high speeds when driving
on an expressway in the rain, because
there may be a layer of water between
the tires and the road surface,
preventing the steering and brakes
from operating properly.
Driving in the rain

08 SIENNA_U (L/O 0801)
462
2008 SIENNA from Aug. ’08 Prod. (OM45455U)
Because of the added load of the trail-
er, your vehicle’s engine may overheat
on hot days (at temperatures over
30C [85 F]) 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” on page 470 in
Section 4.
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”, start the engine. Be sure to keep the brake ped-
al depressed.
2. Shift into gear.
3. Release the parking brake and brake pedal and slowly pull or back away
from the wheel blo cks. Stop and apply
your brakes.
4. Have someone retrieve the blo cks.
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.

08 SIENNA_U (L/O 0801)
463
2008 SIENNA from Aug. ’08 Prod. (OM45455U)
Improving fuel economy 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 page
523 in Section 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 warmup 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.
Put the selector lever into the “D”
when engine braking is not required.
Driving with the selector lever in “4”
will reduce the fuel economy. (For de-
tails, see “Automatic transmission” on
page 205 in Section 1 −7.)
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 lugging or overrev-
ving. 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 premature 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 tunedup 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 “Scheduled
Maintenance Guide” or “Owner ’s Manu-
al Supplement”.)
How to save fuel and make
your vehicle last longer