2003 TOYOTA TUNDRA engine overheat

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2003 TUNDRA from Jul. ’03 Prod. (OM 34430U)
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 Section 4.
IdlingNormal
driving
The oil pressure gauge indicates engine
oil pressure when the ignition switch is
on. Check it while driving to make sure
that the needle is in the proper range.
If the oil pressure should stay below the
normal range, pull off the road to a safe
place and stop the engine immediately.
Call a Toyota dealer or qualified repair
shop for assistance.
Oil pressure may not build up when the
oil level is too low. The oil pressure
gauge is not designed to indicate oil level,
and the oil level must be checked using
the level dipstick.
Oil pressure gauge

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2003 TUNDRA from Jul. ’03 Prod. (OM 34430U)
Fourwheel drive models
5VZFE engine—
Front control lever in “H2” or
“H4” “2” 110 km/h (68 mph) . . . . . . . . .
“L” 60 km/h (37 mph) . . . . . . . . . .
Front control lever in “L4”
“2” 40 km/h (25 mph) . . . . . . . . . .
“L” 20 km/h (12 mph) . . . . . . . . . .
2UZFE engine—
“2WD” or “4HI” mode is selected “2” 120 km/h (75 mph) . . . . . . . . .
“L” 65 km/h (40 mph) . . . . . . . . . .
“4LO” mode is selected “2” 45 km/h (28 mph) . . . . . . . . . .
“L” 25 km/h (16 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.(f) 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.
(g) 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.
(h) Good driving practice
If the transmission repeatedly shifts up
and down between third gear and over-
drive when climbing a gentle slope, the
overdrive should be turned off. Be sure
to turn the switch on immediately after-
ward.
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
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.

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5VZFE engine
2UZFE engine
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 idle or park your vehicle
over anything that might burn easi-
ly 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 minu-
tes.
 Avoid racing the engine.
 Do not pushstart or pullstart your
vehicle.
 Do not turn off the ignition while
the vehicle is moving.
Threeway catalytic converters

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2003 TUNDRA from Jul. ’03 Prod. (OM 34430U)
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. 5VZ −FE engine—With your foot off the
accelerator pedal, crank the engine by
turning the ignition key to “START”
position. Release it when the engine
starts.
2UZ− FE engine—With your foot off the
accelerator pedal, turn the ignition key
to “START” position, then release it.
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 Sec-
tion 4.NOTICE
 5VZFE engine only—Do not crank
for more than 30 seconds 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 such
as a tire burst.
Drive slowly when passing over bumps
or travelling on a bumpy road. Other-
wise, the impact could cause severe
damage to the tires and/or wheels.
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” (automatic) or in first or
reverse (manual). If necessary, block
the wheels.
(b) Starting the engine Tips for driving in various
conditions

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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 applied. If they still do not
work safely, pull to the side of the road
and call a Toyota dealer for assistance.
Four−wheel drive models—Toyota rec-
ommends not using four −wheel drive on
dry hard− surfaced roads, because four −
wheel driving will cause unnecessary
noise and wear, and poor fuel econo-
my.
Four −wheel drive models—In cold tem-
peratures, noise may occur when driv-
ing in two −wheel drive before the trans-
fer is warmed up. Therefore, first drive
in four −wheel drive until the transfer is
warmed up.
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 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.

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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 fifth gear (manual
transmission) or overdrive (automatic
transmission).
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” 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” (automatic)
or in first or reverse (manual). Avoid
parking 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 first or reverse (manual) or “P” (automatic) and turn off the engine.

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When restarting out after parking on a
slope:
1. With the transmission in “P” position (automatic) or the clutch pedal de-
pressed (manual), start the engine.
(With an automatic transmission, be
sure to keep the brake pedal de-
pressed.)
2. Shift into gear.
3. Release the parking brake (also foot brake on automatic transmission ve-
hicles) 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.
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 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.
Always keep the automatic transmis-
sion overdrive switch turned on.
Driving with the overdrive switch off
will reduce the fuel economy. (For de-
tails, see “Automatic transmission” in
Section 1 −6.)
Accelerate slowly and smoothly.
Avoid jackrabbit starts. Get into high
gear as quickly as possible.
How to save fuel and make
your vehicle last longer

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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 clutch
or brake pedal. This causes premature
wear, overheating and poor fuel econo-
my.
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,
improper valve clearance, dirty plugs,
dirty oil and grease, brakes not
adjusted, etc. all lower engine
performance and contribute 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
Manual Supplement”.)
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.