2004 TOYOTA SIENNA maintenance

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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 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”.)
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.

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VEHICLE MAINTENANCE AND CARE
Vehicle maintenance and care
Maintenance requirements442
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General maintenance 443
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Does your vehicle need repairing? 445
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Emissions Inspection and Maintenance (I/M) programs 446
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For scheduled maintenance information, please refer to the “Sched-
uled Maintenance Guide” or “Owner’s Manual Supplement”.
SECTION 6

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Your Toyota vehicle has been designed for
fewer maintenance requirements with long-
er service intervals to save both your time
and money. However, each regular mainte-
nance, as well as day−to −day care, is
more important than ever before to ensure
smooth, trouble− free, safe, and economical
drivings.
It is the owner ’s responsibility to make
sure the specified maintenance, including
general maintenance service, is performed.
Note that both the new vehicle and emis-
sion control system warranties specify that
proper maintenance and care must be per-
formed. See “Owner ’s Warranty Informa-
tion Booklet” or “Owner ’s Manual Supple-
ment” for complete warranty information.
General maintenance
General maintenance items are those day −
to −day care practices that are important to
your vehicle for proper operation. It is the
owner ’s responsib ility to insure that the
general maintenance items are performed
regularly.
These checks or inspections can be done
either by yourself or a qualified technician,
or if you prefer, your Toyota dealer will be
pleased to do them at a nominal cost. Scheduled maintenance
The scheduled maintenance items listed in
the “Scheduled Maintenance Guide” or
“Owner ’s Manual Supplement” are those
required to be serviced at regular inter-
vals.
For details of your maintenance schedule,
read the “Scheduled Maintenance Guide”
or “Owner ’s Manual Supplement”.
It is recommended that any replacement
parts used for maintenance or for the
repair of the emission control system
be Toyota supplied.
The owner may elect to use nonToyota
supplied parts for replacement pur-
poses without invalidating the emission
control system warranty. However, use
of replacement parts which are not of
equivalent quality may impair the effec-
tiveness of the emission control sys-
tems.
You may also elect to have mainte-
nance, replacement, or repair of the
emission control devices and system
performed by any automotive repair es-
tablishment or individual without invali-
dating this warranty. See “Owner’s War-
ranty Information Booklet” or “Owner’s
Manual Supplement” for complete war-
ranty information.Where to go for service?
Toyota technicians are well
−trained spe-
cialists and are kept up to date with the
latest service information through technical
bulletins, service tips, and in −dealership
training programs. They learn to work on
Toyotas before they work on your vehicle,
rather than while they are working on it.
You can be confident that your Toyota
dealer ’s service department performs the
best job to meet the maintenance require-
ments on your vehicle—reliably and eco-
nomically.
Your copy of the repair order is proof that
all required maintenance has been per-
formed for warranty coverage. If any prob-
lems should arise with your vehicle while
under warranty, your Toyota dealer will
promptly take care of it. Again, be sure
to keep a copy of the repair order for any
service performed on your Toyota.
What about doityourself maintenance?
Many of the maintenance items are easy
to do yourself if you have a little mechani-
cal ability and a few basic automotive
tools. Simple instructions for how to per-
form them are presented on page 447 in
Section 7.
Maintenance requirements

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If you are a skilled do−it−yourself mechan-
ic, the Toyota service manuals are recom-
mended. Please be aware that do −it−your-
self maintenance can affect your warranty
coverage. See “Owner ’s Warranty Informa-
tion Booklet” or “Owner ’s Manual Supple-
ment” for the details. Listed below are the general maintenance
items that should be performed as fre-
quently as specified. In addition to check-
ing the items listed, if you notice any
unusual noise, smell or vibration, you
should investigate the cause or take your
vehicle to your Toyota dealer or a quali-
fied service shop immediately. It is recom-
mended that any problem you notice be
brought to the attention of your dealer or
the qualified service shop for their advice.
CAUTION
Make these checks only with ade-
quate ventilation if you run the en-
gine.
IN THE ENGINE COMPARTMENT
Items listed below should be checked
from time to time, e.g. each time when
refueling.
Washer fluid
Make sure there is sufficient fluid in the
tank. See page 479 in Section 7
−3 for
additional information. Engine coolant level
Make sure the coolant level is between
the “FULL” and “LOW” lines on the see
−
through reservoir when the engine is cold.
See page 458 in Section 7 −2 for addition-
al information.
Radiator, condenser and hoses
Check that the front of the radiator and
condenser are clean and not blocked with
leaves, dirt, or insects. See page 460 in
Section 7 −2 for additional information.
Battery electrolyte level
Your Toyota has a maintenance free bat-
tery. You do not have to add distilled wa-
ter. For longer life of the battery, however,
see page 476 in Section 7 −3 for additional
information.
Brake fluid level
Make sure the brake fluid level is correct.
See page 462 in Section 7 −2 for addition-
al information.
Engine oil level
Check the level on the dipstick with the
engine turned off and the vehicle parked
on a level spot. See page 456 in Section
7 −2 for additional information.
General maintenance

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Tire inflation pressure
Check the pressure with a gauge ev-
ery two weeks, or at least once a
month. See page 463 in Section 7−2
for additional information.
Tire surface and wheel nuts
Check the tires carefully for cuts,
damage or excessive wear. See page
466 in Section 7− 2 for additional in-
formation. When checking the tires,
make sure no nuts are missing, and
check the nuts for looseness. Tighten
them if necessary.
Tire rotation
Rotate the tires according to the
maintenance schedule. (For sched-
uled maintenance information, please
refer to the “Scheduled Maintenance
Guide” or “Owner ’s Manual Supple-
ment”.) See page 468 in Section 7 −2
for additional information.Be on the alert for changes in perfor-
mance, sounds, and visual tip −offs that
indicate service is needed. Some impor-
tant clues are as follows:
Engine missing, stumbling, or pinging
Appreciable loss of power
Strange engine noises
A leak under the vehicle (however, wa-
ter dripping from the air conditioning
after use is normal.)
Change in exhaust sound (This may
indicate a dangerous carbon monoxide
leak. Drive with the windows open and
have the exhaust system checked im-
mediately.)
Flat −looking tire; excessive tire squeal
when cornering; uneven tire wear
Vehicle pulls to one side when driving
straight on a level road
Strange noises related to suspension
movement
Loss of brake effectiveness; spongy
feeling brake pedal; pedal almost
touches floor; vehicle pulls to one side
when braking
Engine coolant temperature continually
higher than normal If you notice any of these clues, take your
vehicle to your Toyota dealer as soon as
possible. It probably needs adjustment or
repair.
CAUTION
Do not continue driving with the ve-
hicle unchecked. It could result in se-
rious vehicle damage and possibly
personal injury.
Does your vehicle need
repairing?

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Some states have vehicle emission in-
spection programs which include OBD
(On−Board Diagnostics) che cks.
The OBD system monitors the operation
of the emission control system. When the
OBD system determines that a problem
exists somewhere in the emission control
system, the malfunction indicator lamp
comes on. In this case, your vehicle may
not pass the I/M test and need to be
repaired. Contact your Toyota dealer to
service the vehicle.
Even if the malfunction indicator lamp
does not come on, your vehicle may not
pass the I/M test as readiness codes
have not been set in the OBD system.
Readiness codes are automatically set
during ordinary driving. However, when the
battery is disconnected or run down, the
codes are erased. Also, depending on
your driving habits, the codes may not be
completely set.
Also, if the malfunction indicator lamp had
come on recently due to temporary mal-
function such as a loose fuel tank cap,
your vehicle may not pass the I/M test. The malfunction indicator lamp will go off
after taking several driving trips, but the
error code in the OBD system will not be
cleared unless about 40 trips or more are
taken.
If your vehicle does not pass the I/M test
even the malfunction indicator lamp does
not come on, contact your Toyota dealer
to prepare the vehicle for re
−testing.
Emissions Inspection and
Maintenance (I/M) programs

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DOITYOURSELF MAINTENANCE
Introduction
Engine compartment overview448
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Fuse locations 449
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Do −it− yourself service precautions 450
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Positioning the jack 451
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Parts and tools 453
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SECTION 7 1

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If you perform maintenance by yourself,
be sure to follow the correct procedure
given in this Section.
You should be aware that improper or in-
complete servicing may result in operating
problems.
Performing do−it−yourself maintenance
during the warranty period may affect your
warranty coverage. Read the separate
Toyota Warranty statement for details and
suggestions.
This Section gives instructions only for
those items that are relatively easy for an
owner to perform. As explained in Section
6, there are still a number of items that
must be done by a qualified technician
with special tools.
For information on tools and Sections for
do− it−yourself maintenance, see “Parts
and tools” on page 453 in this Section.
Utmost care should be taken when work-
ing on your vehicle to prevent accidental
injury. Here are a few precautions that
you should be especially careful to ob-
serve:CAUTION
When the engine is running, keep
hands, clothing, and tools away
from the moving fan and engine
drive belts. (Removing rings,
watches, and ties is advisable.)
Right after driving, the engine
compartment—the engine, radiator,
exhaust manifold and spark plug
boots, etc.—will be hot. So be care-
ful not to touch them. Oil, fluids
and spark plugs may also be hot.
If the engine is hot, do not remove
the radiator cap or loosen the drain
plugs to prevent burning yourself.
Do not leave anything that may
burn easily, such as paper or rags,
in the engine compartment.
Do not smoke, cause sparks or al-
low open flames around fuel or the
battery. Their fumes are flammable.
Do not get under your vehicle with
just the body jack supporting it. Al-
ways use automotive jack stands or
other solid supports.
Be sure that the ignition is off if
you work near the electric cooling
fans or radiator grille. With the
ignition on, the electric cooling fans
will automatically start to run if the
engine coolant temperature is high
and/or the air conditioning is on.
Use eye protection whenever you
work on or under your vehicle
where you may be exposed to flying
or falling material, fluid spray, etc.
Used engine oil contains potentially
harmful contaminants which may
cause skin disorders such as in-
flammation or skin cancer, so care
should be taken to avoid prolonged
and repeated contact with it. To re-
move used engine oil from your
skin, wash thoroughly with soap
and water.
Do not leave used oil within the
reach of children.
Dispose of used oil and filter only
in a safe and acceptable manner.
Do not dispose of used oil and fil-
ter in household trash, in sewers or
onto the ground. Call your dealer or
a service station for information
concerning recycling or disposal.
Doityourself service
precautions