2006 TOYOTA 4RUNNER check engine

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Leave the system on during the ordi-
nary driving so that it can operate
when needed.
You may hear a 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 ac-
tive traction control system is in the self −
check mode, but does not indicate a mal-
function.
When the active traction control system is
operating, the following conditions occur:
The system controls the spinning of the
4 wheels. At this time, the slip indica-
tor light blinks.
You may feel vibration or noise in your
vehicle, caused by operation of the
brakes. This indicates the system is
functioning properly.
The slip indicator light comes on for a few
seconds when the ignition key is turned
to “ON”. If the indicator light does not
come on when the ignition is turned on,
contact your Toyota dealer.
The brake actuator temperature increases
during continuous operation of the active
traction control system, the vehicle stabil-
ity control system, the downhill assist con-
trol system and the hill −start assist control
system such as on sli ppery roads. If the
brake actuator temperature becomes too
high while any of the systems is operat-
ing, a buzzer will start to sound intermit-
tently to indicate that the active traction
control system can no longer operate. In
this case, immediately stop your vehicle at
a safe place.
If the system continues to operate, the
buzzer sound changes from intermittent to
continuous. (The continuous buzzer
sounds for about 3 seconds.) At the time, the slip indicator light will
come on and the active traction control
system temporarily stops operating in or-
der to protect the brake actuator. (Al-
though the active traction control system
does not operate, there is no problem to
continue your driving.) The system will be
automatically restored after a short time
and the slip indicator light goes out.

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The vehicle stability control system
helps provide integrated control of the
systems such as antilock brake sys-
tem, traction control, engine control,
etc. This system automatically controls
the output of the brakes or engine to
help prevent the vehicle from skidding
when cornering on a slippery road sur-
face or operating steering wheel abrupt-
ly.
This vehicle stability control activates
when the vehicle speed is more than 15
km/h (9 mph).
You may hear a 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 sys-
tem is in the self−check mode, but does
not indicate a malfunction.CAUTION
Do not rely excessively on the ve-
hicle stability control system. Even
if the vehicle stability control sys-
tem is operating, you must always
drive carefully and attentively to
avoid serious injury. Reckless driv-
ing will result in an unexpected ac-
cident. If the slip indicator light
blinks and an alarm sounds, special
care should be taken while driving.
Only use tires of specified size. The
size, manufacturer, brand and tread
pattern for all 4 tires should be the
same. If you use the tires other
than specified, or different type or
size, the vehicle stability control
system may not function correctly.
When replacing the tires or wheels,
contact your Toyota dealer. (See
“Checking and replacing tires” on
page 427 in Section 72.)
If the vehicle is going to skid during driv-
ing, the slip indicator light blinks and an
alarm sounds intermittently. Special care
should be taken while driving.
If the brake pedal is depressed while the
vehicle stability control system is active,
the brake pedal will become hard at an
earlier position than usual. However, the
brakes will respond to the pedal force if
depressed further.
The slip indicator light comes on for a few
seconds when the ignition key is turned
to “ON”. If the indicator light does not
come on when the ignition is turned on,
contact your Toyota dealer.
Vehicle stability control
system

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NOTICE
If the vehicle height is changed fre-
quently when the vehicle is heavily
loaded, the compressor may over-
heat, causing the vehicle height ad-
justment operation to stop.
 Before you lower the vehicle height
with the height select switch, check
under the vehicle to make sure
nothing to damage the vehicle or
no one to be injured is there and
that the underbody of the vehicle
does not touch the ground.
 After unloading, the height of a ve-
hicle equipped with the rear height
control air suspension becomes
slightly higher than the normal ve-
hicle height. Take sufficient care
where the overhead height is re-
stricted.
 Do not select the “LO” mode in the
bumpy roads. If the underbody of
the vehicle touches the rugged road
surface, the vehicle may be dam-
aged.
(d) Turning off the rear height control
air suspension
To turn off the rear height control air
suspension with the vehicle stopped,
push the “HEIGHT CONTROL OFF”
switch. The height control “OFF” indi-
cator light comes on and the vehicle
height is fixed in the same mode as the
height control switch is pushed.
This status is memorized in the system
even after the engine is stopped.
If you push the switch again, the height
control “OFF” indicator light goes out and
the rear height control air suspension is
turned on.
Even after the rear height control air sus-
pension is turned off with the “HEIGHT
CONTROL OFF” switch, if the vehicle
speed exceeds 30 km/h (19 mph), the
rear height control air suspension automat-
ically selects the “N” mode.

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If you change the vehicle height mode,
the indicator lights change as follows:
When changing the vehicle height from
the “N” mode to “HI”:
1. The “N” mode indicator light goes off and the “HI” mode indicator light blinks.
2. After the vehicle height control reaches the “HI” mode, the “HI” mode indicator
light remains on.
If the underbody of the vehicle has
touched the surface on bumpy roads or
the area around the rear suspension is
coated with ice, the vehicle height cannot
be lowered with the height select switch.
The height control indicator lights change
as follows: 1. The present mode indicator light goes
off and the selected mode indicator
light blinks.
2. The selected mode indicator light goes off. (The vehicle height does not
change.) The present mode indicator
light comes on again.
In this case, even if the vehicle is moved
to its usual location or the ice is removed
and the height select switch is pressed,
vehicle height control cannot be operated.
Turn off the engine once and then restart
it.
Height control “OFF” indicator light:
When the ignition switch is turned on, this
light comes on. If it goes out after a few
seconds, the rear height control air sus-
pension operates correctly. If you push the
“HEIGHT CONTROL OFF” switch, the rear
height control air suspension is turned off.
The height control “OFF” indicator light
comes on.
In the following cases, there is a problem
somewhere in the rear height control air
suspension. Although there is no problem
to continue normal driving, have the rear
height control air suspension checked by
your Toyota dealer as soon as possible.
The height control “OFF” indicator light
does not come on when the ignition
switch is turned on.
The height control “OFF” indicator light
blinks.
(f) Parking and stopping tips
If you immediately stop the engine to park
the vehicle after off −road driving, the ve-
hicle height is lowered slightly as the ve-
hicle becomes cool. When parking, make
sure there is nothing that will be in con-
tact with the underbody of the vehicle.
When you start the engine, the vehicle
returns to the previous height.
If you park the vehicle for a long time,
the vehicle height may be gradually low-
ered. When parking for a long time, make
sure there is nothing that will be in con-
tact with the underbody of the vehicle.
When you start the engine, the vehicle
returns to the previous height.
If you stop the engine, the vehicle height
may change in accordance with the
change in the temperature. When you
start the engine, the vehicle returns to the
previous height.

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The “CRUISE” indicator light remains on
to indicate that the system is still in op-
eration.
To turn the cruise control off, press the
“ON−OFF” button. Make sure the
“CRUISE” indicator light is off.
If the cruise control automatically cancels
out other than for the above cases, have
your vehicle checked by your Toyota deal-
er at the earliest opportunity.
RESUMING THE CRUISE CONTROL
If the cruise control is temporarily can-
celled, the cruising speed can be resumed
by pushing the lever up in the “+ RES”
direction.
Vehicle speed must be above 40 km/h (25
mph).
RESETTING TO A FASTER SPEED
Push the lever up in the “+ RES” direction
and hold it. Release the lever when the
desired speed is attained. While the lever
is held up, the vehicle will gradually gain
speed.
However, a faster way to reset is to ac-
celerate the vehicle and then push the
lever down in the “− SET” direction. RESETTING TO A SLOWER SPEED
Push the lever down in the “
− SET” direc-
tion and hold it. Release the lever when
the desired speed is attained. While the
lever is held down, the vehicle speed will
gradually decrease.
However, a faster way to reset is to de-
press the brake pedal and then push the
lever down in the “− SET” direction.
Even if you downshift from “D” to “4”, with
the cruise control on, engine braking will
not be enabled because the cruise control
is not cancelled. To decrease the vehicle
speed, reset to a slower speed with the
cruise control lever or depress the brake
pedal. If you use the brake pedal, cruise
control is cancelled. CRUISE CONTROL FAILURE WARNING
If the “CRUISE” indicator light flashes
when using the cruise control, press the
“ON
−OFF” button to turn the system off
and then press it again to turn it on.
If any of the following conditions then oc-
curs, there is some trouble in the cruise
control system.
The indicator light does not come on.
The indicator light flashes again.
The indicator light goes out after it
comes on.
If this is the case, contact your Toyota
dealer and have your vehicle inspected.

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The threeway 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 idle or park your vehicle
over anything that might burn easi-
ly such as grass, leaves, paper or
rags.
NOTICE
A large amount of unburned gases
flowing into the threeway 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 pushstart or pullstart 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 systems 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”.
Threeway catalytic converters

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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.
Keep the back door and back win-
dow closed while driving. An open
or unsealed back door and back
window, 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 back
window 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.
Engine exhaust cautions Facts about engine oil
consumption

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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.
Oil consumption: Max. 1.0 L per 1000
km (1.1 qt./600 miles, 0.9 Imp. qt./600
miles)
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 expressway, making it
appear that oil is excessively consumed
after driving at high speeds. 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 420 in Section 7
−2.
Your engine is fitted with iridiumtipped
spark plugs.
NOTICE
Use only iridiumtipped spark plugs.
Do not adjust gaps for engine perfor-
mance or smooth driveability.
Iridiumtipped spark plugs
(4.7 L V8 [2UZFE] engine)