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FUNCTIONS OF ENGINE OIL
Engine oil has the primary functions of lu-
bricating and cooling the inside of the en-
gine,
and plays a major role in maintaining
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 isleft on the cylinder wall when a piston
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 com-
bustion gases during the combustionprocess.
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
depends 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 be-come diluted and make it difficult to
judge the true level accurately.
As an example, if a vehicle is used for re-
peated 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 ap-
pear 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 itappear that oil is excessively consumed
after driving at high speeds.
IMPORTANCE OF ENGINE OIL LEVEL CHECK
One of the most important points in proper vehicle maintenance is to keep the engine
oil at the optimum level so that oil function
will
not be impaired. Therefore, it is essen-
tial that the oil level be checked regularly.
Toyota recommends that the oil level bechecked every time you refuel the vehicle.
Failure to check the oil level
regularly could lead to serious
engine trouble due to insuf ficient oil.
NOTICE
For detailed information on oil level check,
see Checking the engine oil levelº in Chapter 7-2.
Facts about engine oil consumption
94ABSº warning light
This light comes on when the ignition key is turned to the ONº position. After about
3 seconds, the light will go off.
If either of the following conditions occurs, this indicates a malfunction somewhere inthe 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 con-
ventionally. Have your vehicle checked
by your Toyota dealer as soon as pos- sible.
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. When stowing luggage or cargo in the ve-
hicle, observe the following:
Put luggage or cargo in the vehicle
when at all possible. Be sure all itemsare secured in place.
Be careful to keep the vehicle bal-anced. Locating the weight as far
forward as possible helps maintainbalance.
For better fuel economy, do not carry
unneeded weight.
To prevent luggage or packages
from sliding forward during brak-
ing, do not stack anything in the
enlarged trunk room. Keep lug-
gage or packages low, as close to
the floor as possible.
Never allow anyone to ride in the enlarged trunk room. It is not de-
signed for passengers. They
should ride in their seats with their
seat belts properly fastened.
Otherwise, they are much more
likely to suffer serious bodily inju-
ry, in the event of sudden braking
or a collision.
CAUTION!
Brake pad wear limit indicators Luggage stowage precautions