FORD 1998 Expedition - Manual (Page 174)

If you must replace the fuel filler cap, replace it with a genuine
Ford or Motorcraft part. The customer warranty may be void for
any damage to the fuel tank or fuel system if a genuine Ford or
Motorcraft fuel filler cap is not used.
The fuel system may be under pressure. If the fuel filler cap is
venting vapor or if you hear a hissing sound, wait until it stops
before completely removing the fuel filler cap. Otherwise, fuel may
spray out and injure you or others.
If you do not use the proper fuel filler cap, the pressure in the
fuel tank can damage the fuel system or cause it to work
improperly in a collision.
Fuel Filter
Your vehicle is equipped with a fuel filter that is mounted on the
underbody.
For fuel filter replacement, see your dealer or a qualified service
technician. Refer to the Scheduled Maintenance Guide for the
appropriate intervals for changing the fuel filter.
If you replace the fuel filter, replace it with an authorized
Motorcraft part. The customer warranty may be void for any
damage to the fuel system if an authorized Motorcraft fuel filter
is not used.
ESSENTIALS OF GOOD FUEL ECONOMY
Measuring techniques
Your best source of information about actual fuel economy is you, the
driver. You must gather information as accurately and consistently as
possible. Fuel expense, frequency of fillups or fuel gauge readings are
NOT accurate as a measure of fuel economy. We do not recommend
taking fuel economy measurements during the first 1 600 km (1 000
miles) of driving (engine break-in period). You will get a more accurate
measurement after 3 000 km–5 000 km (2 000 miles-3 000 miles).
The advertised fuel capacity of the fuel tank on your vehicle is equal to
the rated refill capacity of the fuel tank as listed in the Refill Capacities
chart in this “Owner Guide.” The advertised capacity is the amount of
the Indicated Capacity and the Empty Reserve combined. Indicated
Maintenance and care
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