FORD 2002 F-150 - Manual (Page 265)

Supercharged engines
Your vehicle is designed to use
“Premium” unleaded gasoline with
an (R+M)/2 octane rating of 91 or
higher for optimum performance.
The use of gasolines with lower
octane ratings may degrade performance. We do not recommend the use
of gasolines labeled as “Premium” in high altitude areas that are sold
with octane ratings of less than 91.
If your engine knocks under any driving conditions while you are using
fuel with the recommended octane rating, see your dealer or a qualified
service technician to prevent any engine damage.
Fuel quality
If you are experiencing starting, rough idle or hesitation driveability
problems during a cold start, try a different brand of “Regular” unleaded
gasoline. “Premium” unleaded gasoline is not recommended (particularly
in the United States) because it may cause these problems to become
more pronounced. If the problems persist, see your dealer or a qualified
service technician.
It should not be necessary to add any aftermarket products to your fuel
tank if you continue to use high quality fuel of the recommended octane
rating. Aftermarket products could cause damage to the fuel system.
Repairs to correct the effects of using an aftermarket product in your
fuel may not be covered by your warranty.
Many of the world’s automakers
issued the World-wide Fuel Charter
that recommends gasoline
specifications to provide improved
performance and emission control
system protection for your vehicle.
Gasolines that meet the World-wide
Fuel Charter should be used when
available. Ask your fuel supplier
about gasolines that meet the
World-wide Fuel Charter. In Canada,
look for fuels that display the Auto Makers’ Choice
௢ logo.
Cleaner air
Ford endorses the use of reformulated “cleaner-burning” gasolines to
improve air quality.
91
(R+M)/2 METHOD
Maintenance and Specifications
265