Facts About Engine Oil Consumption - Toyota 2007 Yaris Sedan Owner's Manual

06 09.07
Keep the trunk lid closed while
D
driving. An open or unsealed trunk
lid may cause exhaust gases to be
drawn into the vehicle.
To allow proper operation of your
D
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
D
vehicle, open the windows
close the trunk lid to ensure plenty
of fresh air enters the vehicle. If
you can smell exhaust fumes even
though there are no other vehicles
in the surrounding area, have your
vehicle checked by your
dealer. Continued inhalation of ex-
haust fumes can lead to death by
gas poisoning.
174
Facts about engine oil
consumption
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.
and
Oil is used to lubricate pistons, piston
D
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
Toyota
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
D
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.
Oil consumption: Max. 1.0 L per 1000
km (1.1 qts./600 miles, 0.9 lmp.qts./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.
2007 YARIS SEDAN from Oct. '06 Prod. (OM52736U)