2003 TOYOTA TUNDRA check engine

’03 TUNDRA_U (L/O 0307)
191
2003 TUNDRA from Jul. ’03 Prod. (OM 34430U)
Keep your engine in good running
order. Malfunctions in the engine
electrical system, electronic ignition
system/distributor ignition system
or fuel systems could cause an ex-
tremely high threeway catalytic
converter temperature.
 If the engine becomes difficult to
start or stalls frequently, take your
vehicle in for a checkup as soon
as possible. Remember, your Toyota
dealer knows your vehicle and its
threeway catalytic converter sys-
tem best.
 To ensure that the threeway 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 “Scheduled Maintenance
Guide” or “Owner ’s Manual Supple-
ment”.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.
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. Have the cause immediately
located and corrected.
Toyota does not recommend occu-
pying the rear cargo area when it
is fitted with a slidein camper,
camper shell or other type cover
while the engine is running. This
caution applies to both driving and
stopped or parked situations with
the engine running. Particular care
should be taken to prevent exhaust
gases from entering camper bodies,
trailers or other enclosures on or
around your vehicle. If exhaust
fumes are detected, open all win-
dows and thoroughly ventilate the
area.
Engine exhaust cautions

’03 TUNDRA_U (L/O 0307)
192
2003 TUNDRA from Jul. ’03 Prod. (OM 34430U)
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. The amount of engine oil consumed de-
pends on the viscosity of the oil, the
quality of the oil and the conditions the
vehicle is driven under.
More oil is consumed by high
−speed driv-
ing and frequent acceleration and decel-
eration.
A new engine consumes more oil, since
its pistons, piston rings and cylinder walls
have not become conditioned.
Oil consumption: Max. 1.0 L per 1000
km (1.1 qt./600 miles, 0.9 lmp. qt./600
miles)
When judging the amount of oil con-
sumption, note that the oil may become
diluted and make it difficult to judge
the true level accurately.
As an example, if a vehicle is used for
repeated short trips, and consumes a nor-
mal amount of oil, the dipstick may not
show any drop in the oil level at all, even
after 1000 km (600 miles) or more. This
is because the oil is gradually becoming
diluted with fuel or moisture, making it
appear that the oil level has not changed.
The diluting ingredients evaporate out
when the vehicle is then driven at high
speeds, as on an expressway, making it
appear that oil is excessively consumed
after driving at high speeds. IMPORTANCE OF ENGINE OIL LEVEL
CHECK
One of the most important points in prop-
er vehicle maintenance is to keep the en-
gine oil at the optimum level so that oil
function will not be impaired. Therefore, it
is essential that the oil level be checked
regularly. Toyota recommends that the oil
level be checked every time you refuel
the vehicle.
NOTICE
Failure to check the oil level regularly
could lead to serious engine trouble
due to insufficient oil.
For detailed information on oil level check,
see “Checking the engine oil level” in Sec-
tion 7
−2.
Facts about engine oil
consumption

’03 TUNDRA_U (L/O 0307)
194
2003 TUNDRA from Jul. ’03 Prod. (OM 34430U)
Effective way to press the ABS brake
pedal: When the anti −lock brake system
function is in action, you may feel the
brake pedal pulsating and hear a noise.
In this situation, to let the anti −lock
brake system work for you, just hold the
brake pedal down more firmly. Do not
pump the brake in a panic stop. This
will result in reduced braking performan-
ce.
The anti −lock brake system becomes op-
erative after the vehicle has accelerated
to a speed in excess of approximately 10
km/h (6 mph). It stops operating when the
vehicle decelerates to a speed below
approximately 5 km/h (3 mph).
Depressing the brake pedal on slippery
road surfaces such as on a manhole cov-
er, a steel plate at a construction site,
joints in a bridge, etc. on a rainy day
tends to activate the anti −lock brake sys-
tem.
You may hear a click or motor sound in
the engine compartment for a few seconds
when the engine is started or just after
the vehicle begins to move. This means
that the anti −lock brake system is in the
self −check mode, and does not indicate a
malfunction. When the antilock brake system is ac-
tivated, the following conditions may
occur. They do not indicate a malfunc-
tion of the system:
You may hear the anti
−lock brake sys-
tem operating and feel the brake pedal
pulsating and the vibrations of the ve-
hicle body and steering wheel. You
may also hear the motor sound in the
engine compartment even after the ve-
hicle is stopped.
At the end of the anti −lock brake sys-
tem activation, the brake pedal may
move a little forward.
CAUTION
Do not overestimate the antilock
brake system: Although the antilock
brake system assists in providing ve-
hicle control, it is still important to
drive with all due care and maintain
a moderate speed and safe distance
from the vehicle in front of you, be-
cause there are limits to the vehicle
stability and effectiveness of steering
wheel operation even with the anti
lock brake system on.
If tire grip performance exceeds its
capability, or if hydroplaning occurs
during high speed driving in the rain,
the antilock brake system does not
provide vehicle control.

’03 TUNDRA_U (L/O 0307)
214
2003 TUNDRA from Jul. ’03 Prod. (OM 34430U)
1. Check the area around the vehicle be-
fore entering it.
2. Adjust seat position, seatback angle, seat cushion angle, head restraint
height and steering wheel angle.
3. Adjust the inside and outside rear view mirrors.
4. Lock all doors.
5. Fasten seat belts. Once you turn the ignition key to “START”
position and release it, the cranking hold
function continues to crank the engine in
“ON” position until it starts.
The function stops cranking the engine
after about 25 seconds maximum if the
engine has not started yet. When you
crank the engine again, wait a few sec-
onds and restart it.
If you hold the key in “START” position,
the function will keep cranking for about
30 seconds maximum. 1. Apply the parking brake firmly.
2. Turn off unnecessary lights and acces-
sories.
3. Manual transmission: Press the clutch
pedal to the floor and shift the trans-
mission into neutral. Hold the clutch
pedal to the floor until the engine is
started. A starter safety device will pre-
vent the starter from operating if the
clutch pedal is not fully depressed.
Automatic transmission: Put the se-
lector lever in “P”. If you need to re-
start the engine while the vehicle is
moving, put the selector lever in “N”.
A starter safety device will prevent the
starter from operating if the selector
lever is in any drive position.
4. Automatic transmission only:
De-
press the brake pedal and hold it to
the floor until driving off.
Before starting the engine How to start the engine—
—Cranking hold function
(2UZFE engine only) (a) Before cranking

’03 TUNDRA_U (L/O 0307)
215
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

’03 TUNDRA_U (L/O 0307)
216
2003 TUNDRA from Jul. ’03 Prod. (OM 34430U)
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.

’03 TUNDRA_U (L/O 0307)
218
2003 TUNDRA from Jul. ’03 Prod. (OM 34430U)
NOTICE
If driving through water, such as
when crossing shallow streams,
first check the depth of the water
and the bottom of the river bed for
firmness. Drive slowly and avoid
deep water.
 Take all necessary safety measures
to ensure that water damage to the
engine or other components does
not occur.
Water entering the engine air intake
will cause severe engine damage.
Water can wash the grease from
wheel bearings, causing rusting and
premature failure, and may also en-
ter the differentials, transmission
and transfer case, reducing the gear
oil’s lubricating qualities.
 Sand and mud that has accumulated
in brake drums and around brake
discs may affect braking efficiency
and may damage brake system com-
ponents.
Always perform a maintenance in-
spection after each day of offroad
driving that has taken you through
rough terrain, sand, mud, or water.
For scheduled maintenance in-
formation, refer to the “Scheduled
Maintenance Guide” or “Owner’s
Manual Supplement”.Make sure your coolant is properly pro-
tected against freezing.
Your coolant must contain ethylene −glycol
type coolant for a proper corrosion
protection of aluminum components. Use
“Toyota Genuine Long Life Coolant” or
equivalent.
See Section 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. Section 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.
Winter driving tips

’03 TUNDRA_U (L/O 0307)
219
2003 TUNDRA from Jul. ’03 Prod. (OM 34430U)
Make sure the engine oil viscosity is
suitable for the cold weather.
See Section 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.
Use a washer fluid containing an anti-
freeze solution.
This product is available at your Toyota
dealer and most auto parts stores. Follow
the manufacturer ’s directions for how
much to mix with water.
NOTICE
Do not use engine antifreeze or any
other substitute because it may dam-
age your vehicle’s paint.
Do not use your parking brake when
there is a possibility it could freeze.
When parking, put the transmission into
“P” (automatic) or into first or reverse
(manual) and block the front wheels. Do
not use the parking brake, or snow or
water accumulated in and around the
parking brake mechanism may freeze,
making it hard to release.
Keep ice and snow from accumulating
under the fenders.
Ice and snow built up under your fenders
can make steering difficult. During bad
winter driving, stop and check under the
fenders occasionally.
Depending on where you are driving,
we recommend you carry some emer-
gency equipment.
Some of the things you might put in the
vehicle are tire chains, window scraper,
bag of sand or salt, flares, small shovel,
jumper cables, etc.
Your vehicle is not designed to be
dinghy towed (with four wheels on the
ground) behind a motorhome.
NOTICE
Do not tow your vehicle with four
wheels on the ground. This may
cause serious damage to your vehicle.
Dinghy towing