Ford F-150 Heritage (2004 year). Manual — part 49

Fuel Filler Cap

Your fuel tank filler cap has an indexed design with a 1/8 turn on/off
feature.

When fueling your vehicle:

1. Turn the engine off.

2. Carefully turn the filler cap counterclockwise 1/8 of a turn until it
stops.

3. Pull to remove the cap from the fuel filler pipe.

4. To install the cap, align the tabs on the cap with the notches on the
filler pipe.

5. Turn the filler cap clockwise 1/8 of a turn until it stops.

If the “Check Fuel Cap”

indicator comes on or if “Service Engine

Soon/Check Engine” indicator comes on and stays on when you start the
engine, the fuel filler cap may not be properly installed. Turn off the
engine, remove the fuel filler cap, align the cap properly and reinstall it.

If you must replace the fuel filler cap, replace it with a fuel filler
cap that is designed for your vehicle. The customer warranty may
be void for any damage to the fuel tank or fuel system if the
correct 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, excessive pressure or
vacuum in the fuel tank may damage the fuel system or cause

the fuel cap to disengage in a collision, which may result in possible
personal injury.

Choosing the right fuel

Use only UNLEADED FUEL. The use of leaded fuel is prohibited by law
and could damage your vehicle.

Your vehicle was not designed to use fuel or fuel additives with metallic
compounds, including manganese-based additives. Studies indicate that
these additives can cause your vehicle’s emission control system to
deteriorate more rapidly. In Canada, premium grade fuel generally

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contains more metallic additives than regular fuel. We recommend using
regular grade fuel. In Canada, many fuels contain metallic additives, but
fuels free of such additives may be available; check with your local fuel
dealer.

Do not use fuel containing methanol. It can damage critical fuel system
components.

Repairs to correct the effects of using a fuel for which your vehicle was
not designed may not be covered by your warranty.

Octane recommendations

Your vehicle is designed to use
“Regular” unleaded gasoline with
pump (R+M)/2 octane rating of 87.
We do not recommend the use of
gasolines labeled as “Regular” that
are sold with octane ratings of 86 or lower in high altitude areas.

Do not be concerned if your engine sometimes knocks lightly. However, if
it knocks heavily under most 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, try a different brand of unleaded gasoline. “Premium”
unleaded gasoline is not recommended for vehicles designed to use
“Regular” unleaded gasoline 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 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.

87

(R+M)/2 METHOD

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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.

If you have run out of fuel:
• You may need to cycle the ignition from OFF to ON several times after

refueling, to allow the fuel system to pump the fuel from the tank to
the engine.

• Your Service engine soon indicator may come on. For more

information on the Service engine soon indicator, refer to the
Instrument cluster chapter.

Fuel Filter

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.

Replace the fuel filter 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 fill-ups 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).

Filling the tank

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
section of this chapter.

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The advertised capacity is the amount of the indicated capacity and the
empty reserve combined. Indicated capacity is the difference in the
amount of fuel in a full tank and a tank when the fuel gauge indicates
empty. Empty reserve is the small amount of fuel remaining in the fuel
tank after the fuel gauge indicates empty.

The amount of usable fuel in the empty reserve varies and should
not be relied upon to increase driving range. When refueling your
vehicle after the fuel gauge indicates empty, you might not be
able to refuel the full amount of the advertised capacity of the
fuel tank due to the empty reserve still present in the tank.

For consistent results when filling the fuel tank:
• Turn the engine/ignition switch to the off position prior to refueling,

an error in the reading will result if the engine is left running.

• Use the same filling rate setting (low — medium — high) each time

the tank is filled.

• Allow no more than 2 automatic click-offs when filling.
• Always use fuel with the recommended octane rating.
• Use a known quality gasoline, preferably a national brand.
• Use the same side of the same pump and have the vehicle facing the

same direction each time you fill up.

• Have the vehicle loading and distribution the same every time.
Your results will be most accurate if your filling method is consistent.

Calculating fuel economy

1. Fill the fuel tank completely and record the initial odometer reading
(in kilometers or miles).

2. Each time you fill the tank, record the amount of fuel added (in liters
or gallons).

3. After at least three to five tank fill-ups, fill the fuel tank and record
the current odometer reading.

4. Subtract your initial odometer reading from the current odometer
reading.

5. Follow one of the simple calculations in order to determine fuel
economy:

Calculation 1: Multiply liters used by 100, then divide by total
kilometers traveled.

Calculation 2: Divide total miles traveled by total gallons used.

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