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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.
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.
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 troubledue to insufficient oil.
For detailed information on oil level check,
see ºChecking the engine oil levelº in
Chapter 7- 2.
Facts about engine oil
consumption
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Your engine is fitted with twin ground
electrode platinum- tipped spark plugs.
NOTICE
Use only twin ground electrode plati- num- tipped spark plugs for your en-gine performance.
Brake system
TANDEM MASTER CYLINDER BRAKE SYSTEM
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 be longer. 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 reserve
vacuum for one or two stopsÐbut no
more!
CAUTION
Do not pump the brake pedal if the
engine stalls. Each push on the
pedal uses up your vacuum reserve.
Even if the power assist is com-
pletely lost, the brakes will still
work. But you will have to push the
pedal hardÐmuch harder than nor-
mal. And your braking distance will
be longer.
ANTI- LOCK BRAKE SYSTEM
(with ºABSº warning light)
The anti- lock brake system is designed to
automatically help prevent lock- up of the
wheels during sudden braking or braking
on slippery road surfaces. This assists in
providing directional stab ility and steering
performance of the vehicle under these
circumstances.
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).
Twin ground electrode
platinum- tipped spark plugs
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You may hear a sound in the engine
compartment for a few seconds when the
engine is started or just after the vehicle
is started. This means that the anti- lock
brake system is in the self check mode,
and does not indicate a malfunction.
Effective way to press the ºABSº 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. Pump-
ing the brake pedal makes the stopping
distance longer.
The brake pedal pulsation caused by the
anti- lock brake system may indicate haz-
ardous road surface conditions. Although
the anti- lock brake system assists in pro-
viding vehicle control, it is still important
to drive with all due care, because the
anti- lock brake system cannot overcome
the laws of physics that act on your ve-
hicle: Braking capab ility is dependent on tire
friction with the road surface.
Even though the anti- lock brake sys-
tem is operating, a driver cannot main-
tain full control on certain slippery road
surfaces, when cornering at high
speeds, or in violent maneuvers.
Avoid high speeds on wet roads. The
anti- lock brake system cannot elimi-
nate the risk of hydroplaning and loss
of tire friction.
Always maintain a safe distance from the
vehicle in front of you. Compared with
vehicles not fitted with an anti- lock brake
system, your vehicle may r equire a longer
stopping distance in the following cases:
Driving on rough, gravel or snow- cov-
ered roads.
Driving with tire chains installed.
Driving on roads where the road sur-
face is pitted or has other differences
in surface height.
CAUTION
Do not use tires other than the
manufacturer 's designated tires, and
do not mix tires or wheels of differ-
ent sizes. You may prevent the anti-
lock brake system from operating at
full effectiveness.
Ty p e A
Ty p e B
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ºABSº warning light
This light comes on when the ignition key
is turned to the ºONº position. After a few
seconds, the light will go off.
If either of the following conditions occurs,
this indicates a malfunction somewhere in
the parts monitored by the warning light
system. Contact your Toyota dealer as
soon as possible to service the vehicle.
The light does not come on as de-
scribed above, or remains on.
The light comes on while driving.
Even if the anti- lock brake system should
fail, the brake system will still operate
conventionally. However, when the ºABSº
warning light is on (and the brake system
warning light is off), anti- lock brake sys-
tem is not assisting brake performance so
that the wheel can lock- up during sudden
braking or braking on slippery road sur-
faces. Have your vehicle checked by your
Toyota dealer as soon as possible. Brake pad wear limit indicators
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.Luggage stowage pr
ecautions
When stowing luggage or cargo in the
vehicle, observe the following: Put luggage or cargo in the luggage
compartment when at all possible. Be
sure all items are secured in place.
Be careful to keep the vehicle bal-
anced. Locating the weight as far for-
ward as possible helps maintain bal-
ance.
For better fuel economy, do not carry
unneeded weight.CAUTION
To prevent luggage or packages
from sliding forward during braking,
do not stack anything in the lug-
gage compartment higher than the
seatbacks. Keep luggage or pack-
ages low, as close to the floor as
possible.
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