1999 TOYOTA SIENNA engine

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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.
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 express way, 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
Chapter 7−2.
Your engine is fitted with twin ground
electrode platinum−tipped spark plugs.
NOTICE
Use only twin ground electrode plati-
num−tipped spark plugs for your en-
gine performance.
Twin ground electrode
platinum−tipped spark plugs
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Brake system
TANDEM MASTER CYLINDER BRAKE
SYSTEM
The tandem master cylinder brake system
is a hydraulic system with two separate
sub−systems. If either sub−system should
fail, the other will still work. However, the
pedal will be harder to press, and your
stopping distance will be longer. Also, the
brake system warning light may come on.
CAUTION
Do not drive your vehicle with only a
single brake system. Have your
brakes fixed immediately.
BRAKE BOOSTER
The brake booster uses engine vacuum to
power−assist the brakes. If the engine
should quit while you are driving, you can
bring the vehicle to a stop with normal
pedal pressure. There is enough reserve
vacuum for one or two stops—but no
more!
CAUTION
Do not pump the brake pedal if the
engine stalls. Each push on the
pedal uses up your vacuum reserve.
Even if the power assist is com-
pletely lost, the brakes will still
work. But you will have to push the
pedal hard—much harder than nor-
mal. And your braking distance will
be longer.
ANTI−LOCK BRAKE SYSTEM (with
”ABS” warning light)
The anti−lock brake system is designed to
automatically help prevent lock−up of the
wheels during sudden braking or braking
on slippery road surfaces. This assists in
providing directional stability and steering
performance of the vehicle under these
circumstances.
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 decelerate to a speed below
approximately 5 km/h (3 mph).You may hear a sound and feel a vibra-
tion in the engine compartment for a few
seconds when the engine is started or just
after the vehicle is started. This means
that the anti−lock brake system is in the
self check mode, and does not indicate a
malfunction.
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. Pump-
ing the brake pedal makes the stopping
distance longer.
The brake pedal pulsation caused by the
anti−lock brake system may indicate haz-
ardous road surface conditions. Although
the anti−lock brake system assists in pro-
viding vehicle control, it is still important
to drive with all due care, because the
anti−lock brake system cannot overcome
the laws of physics that act on your ve-
hicle:
Braking capability is dependent on tire
friction with the road surface.
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The vehicle identification number (VIN)
is the legal identifier for your vehicle.
This number is on the left top of the
instrument panel, and can be seen
through the windshield from outside.
This is the primary identification number
for your Toyota. It is used in registering
the ownership of your vehicle.The vehicle identification number (VIN) is
also on the Certification Label.
—Engine number
The engine number is stamped on the
engine block as shown.
Your Toyota’s identification—
—Vehicle identification
number
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Part 3
STARTING AND
DRIVING
Before starting the engine
How to start the engine
Tips for driving in various
conditions
Winter driving tips
Tr ailer towing
How to save fuel and make
your vehicle last longer, too
Before starting the engine
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 inside and outside rear view
mirrors.
4. Lock all doors.
5. Fasten seat belts.1. Apply the parking brake firmly.
2. Turn off unnecessary lights and acces-
sories.
3. Put the selector lever in ”P”. If you
need to restart the engine while the
vehicle is moving, put the selector le-
ver in ”N”. A starter safety device will
prevent the starter from operating if the
selector lever is in any drive position.
4. Depress the brake pedal and hold it to
the floor until driving off.
How to start the engine—
(a) Before cranking
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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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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.
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” and block the rear wheels. Do not use
the parking brake, or snow or water accu-
mulated 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.
Trailer towing
Your vehicle is designed primarily as a
passenger−and−load−carrying vehicle. Tow-
ing a trailer will have an adverse effect on
handling, performance, braking, durability
and driving economy (fuel consumption,
etc.). Your safety and satisfaction depend
on the proper use of correct equipment
and cautious driving habits. For your safe-
ty and the safety of others, you must not
overload your vehicle or trailer. Ask your
local Toyota dealer for further details be-
fore towing.
WEIGHT LIMITS
Before towing, make sure the total trail-
er weight, gross combination weight,
gross vehicle weight, gross axle weight
and trailer tongue load are all within
the limits.
The total trailer weight and tongue load
can be measured with platform scales
found at a highway weighing station, build-
ing supply company, trucking company,
junk yard, etc.
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A safety chain must always be used
between the towing vehicle and the
trailer. Leave sufficient slack in the
chain for turns. The chain should
cross under the trailer tongue to
prevent the tongue from dropping to
the ground in case it becomes dam-
aged or separated. For correct safety
chain procedures, follow the hitch or
trailer manufacturer ’s recommenda-
tions.
CAUTION
If the total trailer weight exceeds
453 kg (1000 lb.), trailer brakes are
required.
Never tap into your vehicle’s hy-
draulic system as it would lower its
braking effectiveness.
Never tow a trailer without using a
safety chain securely attached to
both the trailer and the vehicle. If
damage occurs to the coupling unit
or hitch ball, there is danger of the
trailer wandering over into another
lane.
TIRES
Ensure that your vehicle’s tires are
properly inflated. Adjust the tire pres-
sure to the recommended cold tire
pressure indicated below (see Chapter
7−2 for instructions.):
Tire pressure, kPa (kgf/cm
2 or bar, psi)
240 (2.4, 35)
The trailer tires should be inflated to
the pressure recommended by the trail-
er manufacturer in respect to the total
trailer weight.
TRAILER LIGHTS
Trailer lights must comply with federal,
state/provincial and local regulations.
See your local recreational vehicle
dealer or rental agency for the correct
type of wiring and relays for your trail-
er. Check for correct operation of the
turn signals and stop lights each time
you hitch up. Direct splicing may dam-
age your vehicle’s electrical system
and cause a malfunction of your lights.BREAK−IN SCHEDULE
Toyota recommends that you do not
tow a trailer with a new vehicle or a
vehicle with any new power train com-
ponent (engine, transmission, differen-
tial, wheel bearing, etc.) for the first
800 km (500 miles) of driving.
MAINTENANCE
If you tow a trailer, your vehicle will
require more frequent maintenance due
to the additional load. For this informa-
tion, please refer to the scheduled
maintenance information in the ”Sched-
uled Maintenance Guide” or ”Owner ’s
Manual Supplement”.
Retighten all fixing bolts of the towing
ball and bracket after approximately
1000 km (600 miles) of trailer driving.
PRE−TOWING SAFETY CHECK
Check that your vehicle remains level
when a loaded or unloaded trailer is
hitched. Do not drive if the vehicle has
an abnormal nose−up or nose−down
condition, and check for improper
tongue load, overload, worn suspension
or other possible causes.
Make sure the trailer cargo is securely
loaded so that it cannot shift.
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