1998 TOYOTA SIENNA check engine

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If your vehicle overheats
If your engine coolant temperature
gauge indicates overheating, if you ex-
perience a loss of power, or if you hear
a loud knocking or pinging noise, the
engine has probably overheated. You
should follow this procedure...
1. Pull safely off the road, stop the ve-
hicle and turn on your emergency
flashers. Put the transmission in ”P”
and apply the parking brake. Turn off
the air conditioning if it is being used.
2. If coolant or steam is boiling out of the
radiator or reservoir,stop the engine.
Wait until the steam subsides before
opening the hood. If there is no coolant
boiling over or steam, leave the engine
running and make sure the electric
cooling fan is operating. If it is not,
turn the ignition off.
CAUTION
To help avoid personal injury, keep
the hood closed until there is no
steam. Escaping steam or coolant is
a sign of very high pressure.
3. Look for obvious coolant leaks from the
radiator, hoses, and under the vehicle.
However, note that water draining from
the air conditioning is normal if it has
been used.
CAUTION
When the engine is running, keep
hands and clothing away from the
moving fan and engine drive belts.
4. If the coolant is leaking, stop the en-
gine immediately. Call a Toyota dealer
for assistance.
5. If there are no obvious leaks, check
the coolant reservoir. If it is dry, add
coolant to the reservoir while the en-
gine is running. Fill it about half full.
CAUTION
Do not attempt to remove the radiator
cap when the engine and radiator are
hot. Serious injury could result from
scalding hot fluid and steam blown
out under pressure.
6. After the engine coolant temperature
has cooled to normal, again check the
coolant level in the reservoir. If neces-
sary, bring it up to half full again. Seri-
ous coolant loss indicates a leak in the
system. You should have it checked as
soon as possible at your Toyota dealer.
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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. And if any
problems 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 do−it−yourself 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 in Part 7.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 Guide, Owner ’s
Manual Supplement or Warranty Booklet
for the details.
General maintenance
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 where ade-
quate ventilation can be obtained if
you run the engine.
OUTSIDE THE VEHICLE
Items listed below should be performed
from time to time, unless otherwise
specified.
Tire pressure
Check the pressure with a gauge every
two weeks, or at least once a month. See
Chapter 7−2 for additional information.
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Tire surface and wheel nuts
Check the tires carefully for cuts, damage
or excessive wear. See Chapter 7−2 for
additional information. 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 every 12000 km (7500
miles). See Chapter 7−2 for additional in-
formation.
Fluid leaks
Check underneath for leaking fuel, oil, wa-
ter or other fluid after the vehicle has
been parked for a while. If you smell fuel
fumes or notice any leak, have the cause
found and corrected immediately.
Doors and engine hood
Check that all doors including trunk lid
operate smoothly and all latches lock se-
curely. Make sure the engine hood sec-
ondary latch secures the hood from open-
ing when the primary latch is released.
INSIDE THE VEHICLE
Items listed below should be checked
regularly, e.g. while performing periodic
services, cleaning the vehicle, etc.Lights
Make sure the headlights, stop lights, tail
lights, turn signal lights, and other lights
are all working. Check headlight aim.
Service reminder indicators and warning
buzzers
Check that all service reminder indicators
and warning buzzers function properly.
Steering wheel
Be alert for changes in steering condition,
such as hard steering or strange noise.
Seats
Check that all seat controls such as seat
adjusters, seatback recliner, etc. operate
smoothly and that all latches lock securely
in any position. Check that the head re-
straints move up and down smoothly and
that the locks hold securely in any latched
position. For folding−down rear seatbacks
and detachable rear seats, check that the
latches lock securely.
Seat belts
Check that the seat belt system such as
buckles, retractors and anchors operate
properly and smoothly. Make sure the belt
webbing is not cut, frayed, worn or dam-
aged.Accelerator pedal
Check the pedal for smooth operation and
uneven pedal effort or catching.
Brake pedal
Check the pedal for smooth operation and
that the pedal has the proper clearance.
Check the brake booster function.
Brakes
At a safe place, check that the brakes do
not pull to one side when applied.
Parking brake
Check that the pedal has the proper travel
and that, on a safe incline, your vehicle
is held securely with only the parking
brake applied.
Automatic transmission ”Park” mecha-
nism
On a safe incline, check that your vehicle
is held securely with the selector lever in
”P” position and all brakes released.
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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 Chapter 7−3 for additional in-
formation.
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 Chapter 7−2 for additional information.
Battery electrolyte level
Make sure the electrolyte level of all bat-
tery cells is between upper and lower lev-
el lines on the case. Add only distilled
water when replenishing. See Chapter 7−3
for additional information.
Brake fluid level
Make sure the brake fluid level is correct.
See Chapter 7−2 for additional information.
Engine oil level
Check the level on the dipstick with the
engine turned off and the vehicle parked
on a level spot. See Chapter 7−2 for addi-
tional information.Power steering fluid level
Check the level through the reservoir. The
level should be in the ”HOT” or ”COLD”
range depending on the fluid temperature.
See Chapter 7−2 for additional information.
Exhaust system
If you notice any change in the sound of
the exhaust or smell exhaust fumes, have
the cause located and corrected immedi-
ately. (See engine exhaust cautions in
Part 2.)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
Does your vehicle need
repairing?
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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.
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.
Do not pry the outer electrode of a
spark plug against the center elec-
trode.
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 platinum−tipped spark
plugs by cleaning or regapping.
Do not overfill automatic transmis-
sion fluid, or the transmission
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.
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Parts and tools
Here is a list of parts and tools you will
need on performing 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):
Engine oil API grade SH,
”Energy−Conserving II” or SJ,
”Energy−Conserving” multigrade or
ILSAC multigrade having viscosity
proper for your climate
Tools:
Rag or paper towel
Funnel (only for adding oil)
Checking the engine coolant level
Parts (if level is low):
Ethylene−glycol antifreeze
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” in Chapter 7−3.)
Tools:
Screwdriver
Wrench
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Part 7
DO−IT−YOURSELF
MAINTENANCE—
Chapter 7−2
Engine and Chassis
Checking the engine oil level
Checking the engine coolant
level
Checking brake fluid
Checking power steering fluid
Checking tire pressure
Checking and replacing tires
Rotating tires
Installing snow tires and chains
Replacing wheels
Aluminum wheel precautions
Checking the engine oil level
Low level Full level
Add oil Too fullO.K.
With the engine at operating tempera-
ture and turned off, check the oil level
on the dipstick.
1. To get a true reading, the vehicle
should be on a level spot. After turning
off the engine, wait a few minutes for
the oil to drain back into the bottom of
the engine.
2. Pull out the dipstick, and wipe it clean
with a rag.
3. Reinsert the dipstick—push it in as far
as it will go, or the reading will not be
correct.
4. Pull the dipstick out and look at the oil
level on the end.
CAUTION
Be careful not to touch the hot ex-
haust manifold.
If the oil level is below or only slightly
above the low level, add engine oil of
the same type as already in the engine.
Remove the oil filler cap and add engine
oil in small quantities at a time, checking
the dipstick.
The approximate quantity of oil needed to
fill between the low level and the full level
on the dipstick is indicated below for ref-
erence.
When the level reaches within the correct
range, install the filler cap hand−tight.
Oil quantity, L (qt., lmp. qt.):
1.5 (1.6, 1.3)
NOTICE
Avoid overfilling, or the engine
could be damaged.
Check the oil level on the dipstick
once again after adding the oil.
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Look at the see−through coolant reser-
voir when the engine is cold. The cool-
ant level is satisfactory if it is between
the ”FULL” and ”LOW” lines on the
reservoir. If the level is low, add ethyl-
ene−glycol type coolant.
The coolant level in the reservoir will vary
with engine temperature. However, if the
level is on or below the ”LOW” line, add
coolant. Bring the level up to the ”FULL”
line.
Use only ethylene−glycol type coolant.
See information in the next column.
If the coolant level drops within a short
time after replenishing, there may be a
leak in the system. Visually check the
radiator, hoses, engine coolant filler cap,
radiator cap and drain cock and water
pump.
If you can find no leak, have your Toyota
dealer test the cap pressure and check
for leaks in the cooling system.
CAUTION
To prevent burning yourself, do not
remove the radiator cap when the en-
gine is hot.
Coolant type selection
Your coolant must contain ethylene−glycol
antifreeze. In addition to preventing freez-
ing and subsequent damage to the engine,
this will also prevent corrosion. Further
supplemental inhibitors or additives are
neither needed nor recommended.
Read the antifreeze container for informa-
tion on freeze protection. Follow the
manufacturer’s directions for how much to
mix with water. The total capacity of the
cooling system is given in Part 8. We
recommend 50% solution be used for your
Toyota, or a sufficient quantity to provide
protection to about −35C (−31F).
NOTICE
Do not use alcohol type antifreeze or
plain water alone.
Checking brake fluid
To check the fluid level, simply look at
the see−through reservoir. The level
should be between the ”MAX” and
”MIN” lines on the reservoir.
It is normal for the brake fluid level to go
down slightly as the brake pads wear. So
be sure to keep the reservoir filled.
If the reservoir needs frequent refilling, it
may indicate a serious mechanical prob-
lem.
If the level is low, add SAE J1703 or
FMVSS No. 116 DOT 3 brake fluid to
the brake reservoir.
Remove and replace the reservoir cover
by hand.
Checking the engine coolant
level
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