2011 Lexus HS250h engine

5
When trouble arises
549
5-2. Steps to take in an emergency
After the hybrid system has cooled
down sufficiently, check the engine
coolant level and inspect the cool-
ing system for leaks.
If the engine compartment cover
needs to be removed. (P. 4 2 9 )
Add engine coolant if necessary.
Water can be used in an emer-
gency if engine coolant is unavail-
able. ( P. 5 6 0 )
Have the vehicle inspected at the ne arest Lexus dealer as soon as possi-
ble.
■ If “HYBRID SYSTEM OVERHEAT” is shown on the multi-informa-
tion display
Stop the vehicle in a safe place and turn off the air conditioning
system.
Leave the hybrid system operating and carefully lift the hood.
Check if the cooling fans are operating.
If the fans are operating:
Wait until the “HYBRID SYSTEM OVERHEAT” message disap-
pears and then stop the hybrid system.
If the message does not disappear, call your Lexus dealer.
If the fans are not operating:
Stop the hybrid system immediately and call your Lexus dealer.

550
5-2. Steps to take in an emergency
After the hybrid system has cooled
down, check the power control
unit coolant level and inspect the
cooling system for leaks.
If the engine compartment cover
needs to be removed. (P. 4 2 9 )
Add power control unit coolant if
necessary.
Water can be used in an emer-
gency if power control unit coolant
is unavailable. ( P. 5 6 0 )
Have the vehicle inspected at the ne arest Lexus dealer as soon as possi-
ble.
■Overheating
The following symptoms may occur wh en your vehicle is overheating:
●The high engine coolant temperature warn ing light comes on or flashes, or the
hybrid system output decreases.
●Steam comes out from the engine area.
●“HYBRID SYSTEM OVERHEAT” is displayed on the multi-information display.

5
When trouble arises
551
5-2. Steps to take in an emergency
CAUTION
■To prevent an accident or injury when inspecting under the hood of your vehicle
●If steam is seen coming from under the hood, do not open the hood until the
steam has subsided. The engine compartm ent may be very hot, causing serious
injuries such as burns.
●Check that the indicator on the “POWER ” switch and the READY indicator are
off.
●For vehicles with a hybrid system, there are times when the gasoline engine auto-
matically starts to run or the cooling fans suddenly start to operate. Do not touch
or approach the rotating parts of the belt or fans. Doing so may lead to fingers,
clothes or tools getting caught, resulting in injury.
●Do not loosen the coolant reservoir cap wh ile the hybrid system and radiator are
hot.
Serious injuries, such as burns, may re sult from hot coolant and steam released
under pressure.
NOTICE
■When adding engine/power control unit coolant
Wait until the hybrid system has cooled down before adding engine/power control
unit coolant.
When adding coolant, do so slowly. Adding cool coolant to a hot hybrid system too
quickly can cause damage to the hybrid system.

557
6-1. Specifications
6
Vehicle specifications
This number is also on the Certifi-
cation Label.
■ Engine number
The engine numbers is stamped on
the engine block as shown.
Engine
Model2AZ-FXE
Ty p e4-cylinder in line, 4-cycle, gasoline
Bore and stroke3.48 3.78 in. (88.5  96.0 mm)
Displacement144.1 cu.in. (2362 cm3)
Drive belt tensionAutomatic adjustment
Valve clearance
(engine cold)Intake: 0.007  0.011 in. (0.19  0.29 mm)
Exhaust: 0.015
 0.019 in. (0.38  0.48 mm)

559
6-1. Specifications
6
Vehicle specifications
■Engine oil selection
“Toyota Genuine Motor Oil” is used in your Lexus vehicle. Use Lexus
approved “Toyota Genuine Motor Oil” or equivalent to satisfy the follow-
ing grade and viscosity.
Oil grade: ILSAC multigrade engine oil
Recommended viscosity: SAE 0W-20
SAE 0W-20 is the best choice for
good fuel economy and good
starting in cold weather.
If SAE 0W-20 is not available,
SAE 5W-20 oil may be used.
However, it must be replaced with
SAE 0W-20 at the next oil
change.
The 0W portion of the oil viscosity rating indicates the characteristic of the oil
which allows cold startability. Oils with a lower value before the W allow for
easier starting of the engine in cold weather.
The 20 in 0W-20 indicates the oil viscosity when the oil is at its operating
temperature. An oil with a higher viscosity may be better suited if the vehicle
is operated at high speeds, or under extreme load conditions.
How to read oil container label:
The ILSAC (International Lubricant St andardization and Approval Com-
mittee) Certification Mark is added to some oil containers to help you
select the oil you should use.
Outside temperature

560
6-1. Specifications
Cooling system
Ignition system
CapacityGasoline engine
Power control unit
7.7 qt. (7.3 L, 6.4 Imp. qt.)
3.1 qt. (2.9 L, 2.6 Imp. qt.)
Coolant type
Use either of the following.• “Toyota Super Long Life Coolant”
• A similar high-quality ethylene glycol-
based non-silicate, non-amine, non-nitrite,
and non-borate coolant with long-life
hybrid organic acid technology
Do not use plain water alone.
Spark plug
Make
GapDENSO SK20R11
NGK IFR6A11
0.043 in. (1.1 mm)
NOTICE
■Iridium-tipped spark plugs
Use only iridium-tipped spark plugs. Do not adjust spark plug gap.

565
6-1. Specifications
6
Vehicle specifications
Fuel information
■Fuel tank opening for unleaded gasoline
To help prevent incorrect fueling, your vehicle has a fuel tank opening that only
accommodates the special nozzle on unleaded fuel pumps.
■Gasoline quality
In very few cases, driveability problems may be caused by the brand of gasoline you
are using. If driveability problems persist, try changing the brand of gasoline. If this
does not correct the problem, consult your Lexus dealer.
■Gasoline quality standards
●Automotive manufacturers in the U.S.A., Europe and Japan have developed a
specification for fuel quality called the World-Wide Fuel Charter (WWFC),
which is expected to be applied worldwide.
●The WWFC consists of four categories that are based on required emission
levels. In the U.S., category 4 has been adopted.
●The WWFC improves air quality by lowering emissions in vehicle fleets, and
improves customer satisfaction through better performance.
■Recommendation of the use of gasoline containing detergent additives
●Lexus recommends the use of gasoline that contains detergent additives to
avoid the build-up of engine deposits.
●All gasoline sold in the U.S.A. contains detergent additives to clean and/or keep
clean intake systems.
You must only use unleaded gasoline in your vehicle.
Select octane rating 87 (Research Octane Number 91) or higher. Use of
unleaded gasoline with an octane rating lower than 87 may result in engine
knocking. Persistent knocking can lead to engine damage.
At minimum, the gasoline you us e should meet the specifications of
ASTM D4814 in the U.S.A. an d CGSB3.5-M93 in Canada.

566
6-1. Specifications
■Recommendation of the use of cleaner burning gasoline
Cleaner burning gasoline, including reformulated gasoline that contains oxygen-
ates such as ethanol or MTBE (Methyl Tertiary Butyl Ether) is available in many
areas.
Lexus recommends the use of cleaner burning gasoline and appropriately blended
reformulated gasoline. These types of gasoline provide excellent vehicle perfor-
mance, reduce vehicle emissions and improve air quality.
■Non-recommendation of the use of blended gasoline
●Lexus allows the use of oxygenate blended gasoline where the oxygenate con-
tent is up to 10% ethanol or 15% MTBE.
●If you use gasohol in your vehicle, be sure that it has an octane rating no lower
than 87.
●Lexus does not recommend the use of gasoline containing methanol.
■Non-recommendation of the use of gasoline containing MMT
Some gasoline contains an octane enhancing additive called MMT (Methylcyclo-
pentadienyl Manganese Tricarbonyl).
Lexus does not recommend the use of gasoli ne that contains MMT. If fuel contain-
ing MMT is used, your emission control system may be adversely affected.
The malfunction indicator lamp on the instrument panel may come on. If this hap-
pens, contact your Lexus dealer for service.
■If your engine knocks
●Consult your Lexus dealer.
●You may occasionally notice light knocking for a short time while accelerating
or driving uphill. This is normal and there is no need for concern.