fuel LEXUS SC300 1999 Service Manual

ENGINE
331
Oil capacity
Drain and refillwith filter
without filter
Oil grade
Recommended oil viscosity (SAE):
4.7 L (5.0 qt., 4.2 lmp.qt.)
4.8 L (5.1 qt., 4.2 lmp.qt.)
API SJ, ºEnergy±Conservingº multigrade engine oil or
ILSAC multigrade engine oil
± COOLING SYSTEM
Capacity
Coolant type
11.6 L (12.3 qt., 10.2 lmp.qt.)
ºToyota Long Life Coolantº or equivalent
With ethylene±glycol type coolant for a proper corrosion
protection of aluminum components
Do not use alcohol type antifreeze or plain water alone.
± FUEL
Fuel type
Octane rating
Only UNLEADED
91 (Research octane number 96) or higher

ENGINE
335
Oil capacity
Drain and refillwith filter
without filter
Oil grade
Recommended oil viscosity (SAE):
5.2 L (5.5 qt., 4.5 lmp.qt.)
4.9 L (5.2 qt., 4.4 lmp.qt.)
API SJ, ºEnergy±Conservingº multigrade engine oil or
ILSAC multigrade engine oil
± COOLING SYSTEM
Capacity
Coolant type
8.4 L (8.9 qt., 7.4 lmp.qt.)
ºToyota Long Life Coolantº or equivalent
With ethylene±glycol type coolant for a proper corrosion
protection of aluminum components
Do not use alcohol type antifreeze or plain water alone.
± FUEL
Fuel type
Octane rating
Only UNLEADED
91 (Research octane number 96) or higher

ENGINE
337
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.

ENGINE
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.

ENGINE
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.

ENGINE
340The amount of engine oil consumed depends on the
viscosity of the oil, the quality of the oil and the way the
vehicle is driven.
More oil is consumed by high±speed driving and frequent
acceleration and deceleration.
A new engine consumes more oil, since its pistons, piston
rings and cylinder walls have not become conditioned.
When judging the amount of oil consumption, keep in
mind that the oil may have become diluted, making it
difficult to judge the true level accurately.
For example, if a vehicle is used for repeated short trips and
consumes a normal 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 proper vehicle
maintenance is to keep the engine oil at the optimum level so
that
oil function will not be impaired. Therefore, it is essential
that the oil level be checked regularly. Lexus 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 ºChecking the
engine oil levelº on page 342.

ENGINE
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.

ENGINE
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

CHASSIS
364The recommended cold tire pressures, tire size and the
vehicle capacity weight are given on the label.
You should check the tire pressures every two weeks, or at
least
once a month. And don't forget the spare! The pressure
for the spare tire should be same with that for the standard tire.
(See page 356 or 358.) Incorrect tire pressure can reduce tire
life and make your vehicle less safe to drive.
Low tire pressure results in excessive wear, poor handling,
reduced fuel economy, and the possibility of blowouts from
overheated tires. Also, low tire pressure can cause poor
sealing of the tire bead. If the tire pressure is excessively low,
there is the possibility of wheel deformation and/or tire
separation. So keep your tire pressures at the proper level. If
a tire needs frequent refilling, have it checked by your Lexus
dealer. High tire pressure produces a harsh ride, handling problems,
excessive wear at the center of the tire tread, and a greater
possibility of tire damage from road hazards.
The following instructions for checking tire pressure should
be observed:

The pressure should be checked only when the tires are
cold. If your vehicle has been parked for at least 3 hours
and has not been driven for more than 1.5 km or 1 mile
since, you will get an accurate cold tire pressure reading.
 Always use a tire pr essure gauge. The appearance of the
tire can be misleading. Besides, tire pressures that are even
just a few pounds off can degrade handling and ride.
 Do not bleed or reduce tire pressure after driving. It is
normal for the tire pressure to be higher after driving.
 Never exceed the vehicle capacity weight. The
passengers and luggage weight should be located so that
the vehicle is balanced.
 Be sure to reinstall the tire valve caps. Without the valve
caps, dirt or moisture could get into the valve core and
cause air leakage. If the caps have been lost, have new
ones put on as soon as possible.

Engine compartment
ELECTRICAL COMPONENTS
377
No.FUSEAMPERECIRCUIT
1ENGINE7.5Charging system
2HTR10Air conditioning system, rear
window defogger
3WIPER20Windshield wipers and washer
4ST7.5
Starting system, cruise control
system, multiport fuel injection
system/sequential multiport fuel
injection system, instrument panel
lights
5IGN7.5
Discharge warning light, multiport
fuel injection system/sequential
multiport fuel injection system,
SRS airbag system
6PANEL7.5Instrument panel lights, glovebox
light
7MIR±HTR10Outside rear view mirror defogger
8TURN7.5Turn signal lights
9STOP15Stop lights, cruise control system
cancel device
10CIG15
Cigarette lighter, theft deterrent
system, shift lock system, SRS
airbag system, instrument panel
lights