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SIENNA_OM_OM08007U_(U)
9-1. Specifications
9
Vehicle specifications
Fuel information
■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..