1999 LEXUS SC300 low

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FUEL
Fuel type
Your vehicle must use only unleaded gasoline.
To help prevent gas station mixups, your Lexus has a smaller
fuel tank opening. The special nozzle on pumps with
unleaded fuel will fit it, but the larger nozzle on pumps with
leaded gas will not.
At a minimum, the gasoline you use should meet the
specifications of ASTM D4814 in the U.S.A. and CGSB
3.5±M93 in Canada.
NOTICE
Do not use leaded gasoline. Use of leaded gasoline will
cause the three±way catalytic converter to lose its
effectiveness and the emission control system to function
improperly. Also, this can increase maintenance costs.
Octane rating
Select premium unleaded gasoline with an Octane Rating
of 91 (Research Octane Number 96) or higher for
optimum engine performance. However, if such premium
type cannot be obtained, you may temporarily use
unleaded gasoline with an Octane Rating as low as 87
(Research Octane Number 91). Use of unleaded fuel with an octane number or rating lower
than stated above will cause persistent heavy knocking. If
severe, this will lead to engine damage.
If your engine knocks ...
If you detect heavy knocking even when using the
recommended fuel, or if you hear steady knocking while
holding a steady speed on level roads, consult your Lexus
dealer.
However, now and then, you may notice light knocking for a
short time while accelerating or driving up hills. This is no
cause for concern.
Gasolines containing detergent additives
Lexus r
ecommends use of gasolines that contain detergent
additives to avoid build±up of engine deposits.
For further details, ask your Lexus dealer or a local gasoline
retailer.
Improved gasolines
The American Automobile Manufacturers Association
(AAMA) has developed a specification of improved
gasolines. The AAMA specification offers optimal fuel
information for better vehicle performance and better
protection of your engine.
Lexus recommends the use of gasolines that meet the AAMA
specification, if available, for improved drivability and
emission control system.

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338
Gasolines containing MTBE
Gasolines that contain MTBE (Methyl Tertiary±Butyl
Ether) are available in the market. If you use a gasoline
mixed with MTBE, make certain that it does not contain
more than 15% of MTBE.
Gasolines containing MMT
Some gasolines contain an octane±enhancing additive
called MMT (methylcyclopentadienyl manganese
tricarbonyl).
Lexus does not recommend the use of gasolines that contain
MMT. If fuels containing MMT are used, your emission
control system may be adversely affected. The Malfunction
Indicator Lamp on the instrument cluster may come on. If this
happens, contact your Lexus dealer for service.
Gasolines containing alcohol
Gasohol is a mixture of gasoline and ethanol. If you use
gasohol in your Lexus, be sure that it is unleaded, has an
octane rating no lower than 87 and does not contain more
than 10% ethanol. Lexus does not recommend the use of
gasolines containing methanol.
If you use gasoline containing methanol, use only gasoline
meeting the requirements above and also containing less than
5% methanol with cosolvents and corrosion inhibitors for
methanol.

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339
Gasolines quality
In a very few cases, you may experience driveability
problems caused by the particular gasoline that you are using.
If you continue to have unacceptable driveability, try
changing gasoline brands. If that does not rectify your
problem, then consult your Lexus dealer.
NOTICE

Do not use gasohol other than stated above. It will
cause fuel system damage or vehicle performance
problems.

If drivability problems are encountered (poor hot
starting, vaporizing, engine knock, etc.), discontinue
its use.

Take care not to spill gasohol during refueling.
Gasohol may cause paint damage.
Fuel tank capacity
78 L (20.6 gal., 17.2 lmp.gal.)
FACTS ABOUT ENGINE OIL
CONSUMPTION
Functions of engine oil
Engine oil has the primary function of lubricating and cooling
the inside of the engine, and plays a major role in maintaining
the engine in proper working order.
Engine oil consumption
It is normal that an engine should consume 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 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 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 temperature exhaust gases also burn the oil
used to lubricate the exhaust valve stems.

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343
4. Pull the dipstick out and look at the oil level on the end.
If it is between the full line (full level mark) and the low line
(low level mark), it is O.K.

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345
If the oil level is below or only slightly above the low line
(low
level mark), add engine oil of the same type as alr eady
in the engine.
Remove the oil filler cap and add engine oil a little at a time,
checking the dipstick. The approximate quantity of oil
needed to fill between the low line (low level mark) and the
full line (full level mark) on the dipstick is indicated below for
reference. When the level reaches within the correct range, return the
filler cap and turn the cap clockwise until you hear a click.
Oil quantity. L (qt., lmp. qt.) SC400, SC300 ± 1.5 (1.6,
1.3)
NOTICE
Avoid
overfilling, or the engine could be damaged. Check
the oil level on the dipstick once again after adding the oil.

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346
Engine oil selection
Use API SJ, ºEnergy±Conservingº multigrade engine oil or
ILSAC multigrade engine oil.
Recommended viscosity (SAE):
SAE 5W±30 is the best choice for your vehicle, for good
fuel economy, and good starting in cold weather.
If you use SAE 10W±30 engine oil in extremely low
temperatures, the engine may become difficult to start, so
SAE 5W±30 engine oil is recommended.

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347
Oil identification marks
Either or both API registered marks are added to some oil
containers to help you select the oil you should use.

The API Service Symbol is located anywhere on the
outside of the container.
The top portion of the label shows the oil quality by API
(American Petroleum Institute) designation such as SJ.
The center portion of the label shows the SAE viscosity
grade such as SAE 5W±30. ºEner gy±Conservingº, shown
in the lower portion, indicates that the oil has fuel±saving
capabilities.

The ILSAC (International Lubricant Standardization and
Approval Committee) Certification Mark is displayed on
the front of the container.CHECKING THE ENGINE
COOLANT LEVEL

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348
Look at the see±through coolant reservoir when the
engine is cold. The coolant level is satisfactory if it is
between theºFULLº and ºLOWº lines on the reservoir.
If the level is low, add ethylene±glycol type coolant for a
proper corrosion protection of aluminum components.
The coolant level in the reservoir will vary with engine
temperature. However, if the level is on or below the ºLOWº
line, add coolant. Bring the level up to the ºFULLº line.
Always use ethylene±glycol type coolant for a proper
corrosion protection of aluminum components. See
information in the next column.If the coolant level drops within a short time after
replenishing, there may be a leak in the system. Visually
check the radiator, hoses, engine coolant filler cap, radiator
cap and drain cock and water pump.
If you can find no leak, have your Lexus dealer test the cap
pressure and check for leaks in the cooling system.
CAUTION
To prevent burning yourself, do not remove the radiator cap
when the engine is hot.