2008 TOYOTA SIENNA check engine

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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 threeway catalytic
converter temperature.
 If the engine becomes difficult to
start or stalls frequently, take your
vehicle in for a checkup as soon
as possible. Remember, your Toyota
dealer knows your vehicle and its
threeway catalytic converter sys-
tem best.
 To ensure that the threeway 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 “Scheduled Maintenance
Guide” or “Owner ’s Manual Supple-
ment”.CAUTION
Exhaust gases include harmful car-
bon monoxide (CO) that is colorless
and odorless. Inhaling exhaust
gases may lead to death or a seri-
ous health hazard.
The exhaust should be checked
occasionally. If there is a hole or
crack caused by corrosion, damage
to a joint or abnormal exhaust
noise, be sure to have the vehicle
inspected and repaired by your
Toyota dealer. Failure to do so may
allow exhaust gases to enter the
vehicle, resulting in death or a
serious health hazard.
If the vehicle is in a poorly venti-
lated area, turn the engine off. In
a closed area, such as a garage,
exhaust gases may collect and en-
ter the vehicle. This may lead to
death or a serious health hazard.
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.
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 the smell of exhaust is noticed
inside the vehicle, open the win-
dows. Large amounts of exhaust in
the vehicle can cause driver drowsi-
ness and an accident, resulting in
death or a serious health hazard.
Have the vehicle inspected by your
Toyota dealer immediately.
Engine exhaust cautions

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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” on
page 518 in Section 7−2.
Long reach
type
Your engine is fitted with long reach
iridiumtipped spark plugs.
NOTICE
Use only Toyota genuine long reach
iridiumtipped spark plugs and do not
adjust gaps for your engine perfor-
mance and smooth driveab ility.
For details about the spark plug type, see
“Service specifications” on page 550 in
Section 8. The tandem master cylinder brake system
is a hydraulic system with two separate
sub
−systems. If either sub −system s hould
fail, the other will still work. However, the
pedal will be harder to press, and your
stopping distance will increase. 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 reserved
vacuum for one or two stops—but no
more!
Long r each iridiumtipped
spark plugs Brake system

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CAUTION
Do not pump the brake pedal if the
engine stalls. Each push on the
pedal uses up your reserved vacu-
um.
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
increase.
ANTILOCK BRAKE SYSTEM (with
“ABS” warning light)
The antilock brake system is designed
to help prevent lockup of the wheels
during a sudden braking or braking on
slippery road surfaces. This assists in
providing directional stability and steer-
ing performance of the vehicle under
these circumstances.
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. This
will result in reduced braking performan-
ce.
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 decelerates to a speed below
approximately 5 km/h (3 mph).
Depressing the brake pedal on slippery
road surfaces such as on a manhole cov-
er, a steel plate at a construction site,
joints in a bridge, etc. on a rainy day
tends to activate the anti −lock brake sys-
tem.
You may hear a click or motor sound in
the engine compartment for a few seconds
when the engine is started or just after
the vehicle begins to move. This means
that the anti −lock brake system is in the
self −check mode, and does not indicate a
malfunction. When the antilock brake system is ac-
tivated, the following conditions may
occur. They do not indicate a malfunc-
tion of the system:
You may hear the anti
−lock brake sys-
tem operating and feel the brake pedal
pulsating and the vibrations of the ve-
hicle body and steering wheel. You
may also hear the motor sound in the
engine compartment even after the ve-
hicle is stopped.
At the end of the anti −lock brake sys-
tem activation, the brake pedal may
move a little forward.

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The light does not come on when the
engine switch is turned to the “ON”
position, or remains on.
The light comes on while you are driv-
ing.
A warning light turning on briefly during
operation does not indicate a problem.
CAUTION
If the “ABS” warning light remains on
together with the brake system warn-
ing light, immediately stop your ve-
hicle at a safe place and contact your
Toyota dealer.
In this case, not only the antilock
brake system will fail but also the
vehicle will become extremely unsta-
ble during braking.
DRUMINDISC TYPE PARKING BRAKE
SYSTEM (with rear disc brake)
Your vehicle has a drum −in −disc type
parking brake system. This type of brake
system n eeds bedding −down of the brake
shoes periodically or whenever the parking
brake shoes and/or drums are replaced.
Have your Toyota dealer perform the bed-
ding− down. BRAKE ASSIST SYSTEM
When you slam the brakes on, the
brake assist system judges as an emer-
gency stop and provides more powerful
braking for a driver who cannot hold
down the brake pedal firmly.
When you slam the brakes on, more pow-
erful braking will be applied. At this time,
you may hear a sound in the engine
compartment and feel the vibrations of the
brake pedal. This does not indicate a mal-
function.
Vehicles with the vehicle stability control
system—
The brake assist system becomes opera-
tive after the vehicle has accelerated to
a speed in excess of approximately 10
km/h (6 mph). It stops operating when the
vehicle decelerates to a speed below
approximately 5 km/h (3 mph).
For an explanation of this system’s warn-
ing light, see “Service reminder indicators
and warning buzzers” on page 191 in Sec-
tion 1
−6.
The brake pad wear limit indicators on
your disc brakes give a warning noise
when the brake pads are worn to where
replacement is required.
If you hear a squealing or scraping noise
while driving, have the brake pads
checked and replaced by your Toyota
dealer as soon as possible. Expensive ro-
tor damage can result if the pads are not
replaced when necessary.
Brake pad wear limit
indicators

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1. Check the area around the vehicle be-fore entering it.
2. Adjust seat position, seatback angle, seat cushion height, head restraint
height and steering wheel angle.
3. Adjust the inside and outside rear view mirrors.
4. Lock all doors.
5. Fasten seat belts. Once you turn the engine switch to
“START” position and release it, the crank-
ing hold function continues to crank the
engine in “ON” position until it starts.
The function stops cranking the engine
after about 25 seconds maximum if the
engine has not started yet. When you
crank the engine again, wait a few sec-
onds and restart it.
If you hold the engine switch in “START”
position, the function will keep cranking
for about 30 seconds maximum. 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.
Before starting the engine How to start the engine—
—Cranking hold function
(a) Before cranking

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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:
With your foot off the accelerator pedal,
crank the engine by turning the engine
switch to “START”. Release it when the
engine starts.
Engine should be warmed up by driving,
not in idle. For warming up, drive with
smoothly turning engine until engine cool-
ant temperature is within normal range.
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” on page
466 in Section 4.NOTICE
 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 such
as a tire burst.
Drive slowly when passing over bumps
or travelling on a bumpy road. Other-
wise, the impact could cause severe
damage to the tires and/or wheels.
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 applied. If they still do not
work safely, pull to the side of the road
and call a Toyota dealer for assistance.
(b) Starting the engine Tips for driving in various
conditions

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CAUTION
Sudden braking, acceleration and
steering when driving on a slippery
road surface may cause tire slip-
page and reduce your ability to
control the vehicle, resulting in an
accident.
Sudden changes in engine speed,
such as sudden engine braking,
may cause the vehicle to skid, re-
sulting in an accident.
After driving through a puddle,
lightly depress the brake pedal to
make sure that the brakes are func-
tioning properly. Wet brake pads
may prevent the brakes from func-
tioning properly. If the brakes on
only one side are wet and not func-
tioning properly, steering control
may be affected, resulting in an ac-
cident.
When encountering flooded roads
Do not drive on a road that has flooded
after heavy rain etc. Doing so may cause
serious damage to the vehicle.
NOTICE
Driving on a flooded road may cause
the engine to stall as well as cause
serious vehicle malfunctions such as
shorts in electrical components and
engine damage from water immersion.
In the event that you drive on a
flooded road and the vehicle is
flooded, be sure to have your Toyota
dealer check brake function, changes
in quantity and quality of oil and fluid
used for the engine, transaxle, trans-
fer (AWD vehicles), differential, etc.
and lubricant condition for the propel-
ler shaft (AWD vehicles), bearings and
suspension joints (where possible)
and the function of all joints and bea-
rings.
If you need greater traction while driv-
ing on sand, mud or snow covered
roadways, use tire chains on the front
wheels.
Always check your brakes for effective-
ness immediately after driving across
sand, mud, or water.
If operating in adverse conditions
frequently, vehicle maintenance should
be increased. (See the separate
“Scheduled Maintenance Guide” or
“Owner ’s Manual Supplement”.)
CAUTION
Observe the following tire instruc-
tions. Otherwise, an accident may oc-
cur resulting in death or serious inju-
ries.
Keep your tire inflation pressure at
the proper level. (See “Checking
tire inflation pressure” on page 523
in Section 72.)
Do not use tires (including snow
tires) of different brands, sizes,
construction or tread patterns. (See
“Checking and replacing tires” on
page 526 and “Installing snow tires
and chains” on page 530 in Section
72.)
Allwheel driving tips
(AWD models)

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Do not use tires with different tread
wear. To equalize the tire wear, ro-
tate tires at the appropriate interval.
(See “Rotating tires” on page 528
in Section 72.)
Use the manufacturer ’s recom-
mended wheels. Do not use wheels
of different sizes and types. (See
“Replacing wheels” on page 532 in
Section 72.)
NOTICE
Do not attempt to go offroad in your
Toyota. It is not designed for offroad
use.
Make sure your coolant is properly pro-
tected against freezing.
Only use “Toyota Super Long Life Coolant”
or similar high quality ethylene glycol
based non−silicate, non −amine, non −nitrite,
and non− borate coolant with long −life
hybrid organic acid technology. (Coolant
with long −life hybrid organic acid
technology is a combination of low
phosphates and organic acids.)
See “Checking the engine coolant level”
on page 520 in Section 7 −2 for details of
coolant type selection.
For the U.S.A.—“Toyota Super Long Life
Coolant” is a mixture of 50% coolant and
50% deionized water. This coolant pro-
vides protection down to about −35 C
( − 31 F).
For Canada—“Toyota Super Long Life
Coolant” is a mixture of 55% coolant and
45% deionized water. This coolant pro-
vides protection down to about −42 C
( − 44 F).
NOTICE
Do not use plain water alone.
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. Section 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.
Make sure the engine oil viscosity is
suitable for the cold weather.
See page 518 in Section 7 −2 for recom-
mended viscosity. Leaving a heavy sum-
mer oil in your vehicle during winter
months may cause harder starting. If you
are not sure about which oil to use, call
your Toyota dealer—they 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.
Winter driving tips