Ford 2003 Explorer Owner's Manual page 244

Maintenance and Specifications
powertrain damage, a loss of vehicle performance, and your
warranty may be invalidated.
Fuel quality
Many of the world's automakers approved 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.
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 an FFV, check
your VIN or the label on the inside of your fuel filler door. When
checking the VIN, look for the engine type identifier (8th character). If
your vehicle is an FFV, then the character will be labeled as a "K."
If you operate your vehicle 50% or more of the time on ethanol, you
should follow a different maintenance schedule. See the Scheduled
Maintenance Guide for more information.
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.
243
2003 Explorer (exp)
Owners Guide (post-2002-fmt)
USA English (fus)