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SIENNA_OM_01999-08001_(U)
9-1. Specifications
9
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 gaso-
line you are using. If driveability problems persist, try changing the brand of
gasoline. If this does not correct the problem, consult your Toyota dealer.
■ Gasoline quality standards
●Automotive manufacturers in the U.S.A., the Europe and Japan have devel-
oped a specification for fuel quality called 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 gaso line containing detergent additives
● Toyota recommends the use of gasoline that contains detergent additives to
avoid build-up of engine deposits.
● All gasoline sold in the U.S.A. contains minimum detergent additives to
clean and/or keep clean intake systems, EPA’s lowest additives concentra-
tion program.
● Toyota strongly recommends the use of Top Tier Detergent Gasoline. For
more information on Top Tier Detergent Gasoline and a list of marketers,
please go to the official website www.toptiergas.com.
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 use s hould meet the specifications of
ASTM D4814 in the U.S.A..
