1998 TOYOTA SIENNA engine

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NOTICE
Do not use gasohol other than
stated above. It will cause fuel sys-
tem damage or vehicle performance
problems.
If driveability problems occur (poor
hot starting, vaporizing, engine
knock, etc.), discontinue the use.
Take care not to spill gasohol dur-
ing refueling. Gashol may cause
paint damage.
FUEL TANK CAPACITY
79 L (21 gal., 17.5 lmp. gal.)
Operation in foreign countries
If you plan to drive your Toyota in
another country...
First, comply with the vehicle registration
laws.
Second, confirm the availability of the cor-
rect fuel (unleaded and minimum octane
number).
Three−way catalytic converter
The three−way 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.
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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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Keep the back door and quarter
windows closed while driving. An
open or unsealed back door and
quarter windows may cause exhaust
gases to be drawn 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 and the back door and quarter
windows closed. Have the cause im-
mediately located and corrected.
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.
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.
Facts about engine oil
consumption
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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.
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!
Twin ground electrode
platinum−tipped spark plugs
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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. This will result in re-
duced braking performance.
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.
Even though the anti−lock brake sys-
tem is operating, a driver cannot main-
tain full control on certain slippery road
surfaces, when cornering at high
speeds, or in violent maneuvers.
Avoid high speeds on wet roads. The
anti−lock brake system cannot elimi-
nate the risk of hydroplaning and loss
of tire friction.
Always maintain a safe distance from the
vehicle in front of you. Compared with
vehicles not fitted with an anti−lock brake
system, your vehicle may require a longer
stopping distance in the following cases:
Driving on rough, gravel or snow−cov-
ered roads.
Driving with tire chains installed.
Driving on roads where the road sur-
face is pitted or has other differences
in surface height.
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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 new vehicle carries theft preven-
tion labels which are approximately 56
mm (2.20 in.) by 16 mm (0.63 in.).
The purpose of these labels is to reduce
the incidence of vehicle thefts by facilitat-
ing the tracing and recovery of parts from
stolen vehicles. The label is designed so
that once it is applied to a surface, any
attempt to remove it will result in destroy-
ing the integrity of the label. Transferring
these labels intact from one part to anoth-
er, will be impossible.NOTICE
You should not attempt to remove the
theft prevention labels as it may vio-
late certain state or federal laws.
Theft prevention labels
(except for Canada)
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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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