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6-1. Specifications
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Fuel information
n Fuel tank opening for unleaded gasoline
To help prevent incorrect fueling, your Toyota has a fuel tank opening that
only accommodates the special nozzle on unleaded fuel pumps.
n If your engine knocks
l Consult your Toyota dealer.
l You may occasionally notice light knocking for a short time while acceler-
ating or driving uphill. This is normal and there is no need for concern.
n Gasoline quality
In very few cases, driveability problems may be caused by the brand of gas-
oline you are using. If driveability problems persist, try changing the brand of
gasoline. If this does not correct the problem, consult your Toyota dealer.
n Gasoline quality standards
l Automotive manufacturers in the US, Europe and Japan have developed
a specification for fuel quality called World-Wide Fuel Charter (WWFC)
that is expected to be applied worldwide.
l The WWFC consists of four categories that are based on required emis-
sion levels. In the US, category 4 has been adopted.
l The WWFC improves air quality by lowering emissions in vehicle fleets,
and customer satisfaction through better performance.
n Toyota recommends the use of gasoline containing detergent additives
l Toyota recommends the use of gasoline that contains detergent additives
to avoid build-up of engine deposits.
l All gasoline sold in the US contains detergent additives to clean and/or
keep clean intake systems.
Your vehicle must use only unleaded gasoline.
Unleaded gasoline with an Octane Rating 87 (Research Octane Num-
ber 91) or higher required for optimum engine performance.
At minimum, the gasoline you use should meet the specifications
of ASTM D4814 in the U.S.A. and CGSB3.5-M93 in Canada.