2004 TOYOTA SIENNA engine

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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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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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1. Power steering fluid reservoir
2. Windshield and rear window washerfluid tank
3. Engine oil level dipstick
4. Engine coolant reservoir
5. Engine oil filler cap
6. Brake fluid reservoir
7. Fuse block
8. Battery
9. Electric cooling fans
10. Condenser
11. Radiator
Engine compartment overview

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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

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Be extremely cautious when work-
ing on the battery. It contains poi-
sonous and corrosive sulfuric acid.
NOTICE
Remember that battery and ignition
cables carry high currents or volt-
ages. Be careful of accidentally
causing a short circuit.
 Add only demineralized or distilled
water to fill the radiator. And if you
spill some of the coolant, be sure
to wash off with water to prevent it
from damaging the parts or paint.
 Do not allow dirt or anything else
to fall through the spark plug holes.
 Use only spark plugs of the speci-
fied type. Using other types will
cause engine damage, loss of per-
formance or radio noise.
Do not reuse iridiumtipped spark
plugs by cleaning or regapping.
 Do not overfill automatic transmis-
sion fluid and power steering fluid,
or the transmission and power
steering could be damaged.
 Do not drive with the air cleaner
filter removed, or excessive engine
wear could result. Also backfiring
could cause a fire in the engine
compartment.
 Be careful not to scratch the glass
surface with the wiper frame.
 When closing the engine hood,
check to see that you have not for-
gotten any tools, rags, etc.
Front
Rear (twowheel drive models)
Positioning the jack

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Rear (allwheel drive models)
When jacking up your vehicle with the
jack, position the jack correctly as
shown in the illustrations.
CAUTION
When jacking, be sure to observe the
following to reduce the possibility of
personal injury:
Follow jacking instructions.
Do not put any part of your body
under the vehicle supported by the
jack. Personal injury may occur.
Do not start or run the engine while
your vehicle is supported by the
jack.
Stop the vehicle on a level firm
ground, firmly set the parking brake
and put the transmission in “P”.
Block the wheels on the opposite
side of the jack up point if neces-
sary.
Make sure to set the jack properly
in the jack point. Raising the ve-
hicle with jack improperly posi-
tioned will damage the vehicle or
may allow the vehicle to fall off the
jack and cause personal injury.
Never get under the vehicle when
the vehicle is supported by the jack
alone; use vehicle support stands.
Do not raise the vehicle with some-
one in the vehicle.
When raising the vehicle, do not
place any objects on top of or un-
derneath the jack.
NOTICE
Make sure to place the jack correctly,
or your vehicle may be damaged.

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Here is a list of parts and tools you will
need to perform do−it−yourself mainte-
nance. Remember all Toyota parts are de-
signed in metric sizes, so your tools must
be metric.
CHECKING THE ENGINE OIL LEVEL
Parts (if level is low):
“Toyota Genuine Motor Oil” or equiva-
lent
See page 456 in Section 7 −2 for de-
tails about engine oil selection.
Tools:
Rag or paper towel
Funnel (only for adding oil)
CHECKING THE ENGINE COOLANT
LEVEL
Parts (if level is low):
“Toyota Genuine Long Life Coolant” or
equivalent
See page 458 in Section 7 −2 for de-
tails about coolant type selection.
Demineralized or distilled water
Tools:
Funnel (only for adding coolant) CHECKING BRAKE FLUID
Parts (if level is low):
SAE J1703 or FMVSS No.116 DOT 3
brake fluid
Tools:
Rag or paper towel
Funnel (only for adding fluid)
CHECKING POWER STEERING FLUID
Parts (if level is low):
Automatic transmission fluid
DEXRON®II or III
Tools:
Rag or paper towel
Funnel (only for adding fluid)
CHECKING BATTERY CONDITION
Tools:
Warm water
Baking soda
Grease
Conventional wrench (for terminal
clamp bolts) CHECKING AND REPLACING FUSES
Parts (if replacement is necessary):
Genuine Toyota fuse or equivalent with
same amperage rating as original
ADDING WASHER FLUID
Parts:
Water
Washer fluid containing antifreeze (for
winter use)
Tools:
Funnel
REPLACING LIGHT BULBS
Parts:
Bulb with same number and wattage
rating as original (See charts in
“Replacing light bulbs” on page 480 in
Section 7 −3.)
Tools:
Screwdriver
Wrench
Parts and tools

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DOITYOURSELF MAINTENANCE
Engine and Chassis
Checking the engine oil level456
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Checking the engine coolant level 458
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Checking the radiator and condenser 460
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Checking and replacing the air conditioning filter 460
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Checking brake fluid 462
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Checking power steering fluid 463
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Checking tire inflation pressure 463
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Checking and replacing tires 466
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Rotating tires 468
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Run −flat tires 469
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Installing snow tires and chains 471
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Replacing wheels 473
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Aluminum wheel precautions 474
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SECTION 7 2