FORD 2002 Explorer v.1 - Manual (Page 263)

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.
Unleaded Gasoline engines
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.
FFV engine (if equipped)
Your FFV will operate well on ordinary “Regular” unleaded gasoline, but
only the highest quality fuel ethanol will provide the same level of
protection and performance. To identify if your vehicle is a FFV, check
your VIN or the label on the inside of your fuel filler door.
Standards for fuel ethanol have been developed to provide FFVs the best
possible performance, safety and durability. To assist alcohol fuel
providers in meeting these standards, guidelines have also been
developed which prescribe “Ethanol Fuel Compatible” dispensing station
equipment. These standards and guidelines can be obtained from Ford
Motor Company. Fuel stations may apply to be certified as meeting these
standards. However, not all stations meet these standards at this time. To
ensure proper operation of your FFV on fuel ethanol, refuel at certified
stations.
If you are experiencing a rough or rolling idle after start-up with the
outside temperature above 27° C (80° F), the idle should improve within
10 to 30 seconds. If the problems persist below this temperature, see
your dealer or a qualified service technician.
Cleaner air
Ford endorses the use of reformulated “cleaner-burning” gasolines to
improve air quality.
Running out of fuel
Avoid running out of fuel because this situation may have an adverse
affect on powertrain components.
Maintenance and care
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