Ford Thunderbird (2004 year). Manual — part 44

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.
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).

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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.

Keep a record for at least one month and record the type of driving (city
or highway). This will provide an accurate estimate of the vehicle’s fuel
economy under current driving conditions. Additionally, keeping records
during summer and winter will show how temperature impacts fuel
economy. In general, lower temperatures give lower fuel economy.

Driving style — good driving and fuel economy habits

Give consideration to the lists that follow and you may be able to change
a number of variables and improve your fuel economy.

Habits
• Smooth, moderate operation can yield up to 10% savings in fuel.
• Steady speeds without stopping will usually give the best fuel

economy.

• Idling for long periods of time (greater than one minute) may waste

fuel.

• Anticipate stopping; slowing down may eliminate the need to stop.
• Sudden or hard accelerations may reduce fuel economy.
• Slow down gradually.
• Driving at reasonable speeds (traveling at 88 km/h [55 mph] uses 15%

less fuel than traveling at 105 km/h [65 mph]).

• Revving the engine before turning it off may reduce fuel economy.
• Using the air conditioner or defroster may reduce fuel economy.
• You may want to turn off the speed control in hilly terrain if

unnecessary shifting between fourth and fifth gear occurs.
Unnecessary shifting of this type could result in reduced fuel
economy.

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• Warming up a vehicle on cold mornings is not required and may

reduce fuel economy.

• Resting your foot on the brake pedal while driving may reduce fuel

economy.

• Combine errands and minimize stop-and-go driving.
Maintenance
• Keep tires properly inflated and use only recommended size.
• Operating a vehicle with the wheels out of alignment will reduce fuel

economy.

• Use recommended engine oil. Refer to Lubricant specifications in

this chapter.

• Perform all regularly scheduled maintenance items. Follow the

recommended maintenance schedule and owner maintenance checks
found in your vehicle scheduled maintenance guide.

Conditions
• Heavily loading a vehicle or towing a trailer may reduce fuel economy

at any speed.

• Carrying unnecessary weight may reduce fuel economy (approximately

0.4 km/L [1 mpg] is lost for every 180 kg [400 lb] of weight carried).

• Adding certain accessories to your vehicle (for example bug

deflectors, rollbars/light bars, running boards, ski/luggage racks) may
reduce fuel economy.

• Using fuel blended with alcohol may lower fuel economy.
• Fuel economy may decrease with lower temperatures during the first

12–16 km (8–10 miles) of driving.

• Driving on flat terrain offers improved fuel economy as compared to

driving on hilly terrain.

• Transmissions give their best fuel economy when operated in the top

cruise gear and with steady pressure on the gas pedal.

• Four-wheel-drive operation (if equipped) is less fuel efficient than

two-wheel-drive operation.

• Close windows for high speed driving.

EPA window sticker

Every new vehicle should have the EPA window sticker. Contact your
dealer if the window sticker is not supplied with your vehicle. The EPA
window sticker should be your guide for the fuel economy comparisons
with other vehicles.

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It is important to note the box in the lower left corner of the window
sticker. These numbers represent the Range of L/100 km (MPG)
expected on the vehicle under optimum conditions. Your fuel economy
may vary depending upon the method of operation and conditions.

EMISSION CONTROL SYSTEM

Your vehicle is equipped with various emission control components and a
catalytic converter which will enable your vehicle to comply with
applicable exhaust emission standards. To make sure that the catalytic
converter and other emission control components continue to work
properly:
• Use only the specified fuel listed.
• Avoid running out of fuel.
• Do not turn off the ignition while your vehicle is moving, especially at

high speeds.

• Have the items listed in your scheduled maintenance guide performed

according to the specified schedule.

The scheduled maintenance items listed in the scheduled maintenance
guide are essential to the life and performance of your vehicle and to its
emissions system.

If other than Ford, Motorcraft or Ford-authorized parts are used for
maintenance replacements or for service of components affecting
emission control, such non-Ford parts should be equivalent to genuine
Ford Motor Company parts in performance and durability.

Do not park, idle, or drive your vehicle in dry grass or other dry
ground cover. The emission system heats up the engine

compartment and exhaust system, which can start a fire.

Illumination of the “Check Engine” light, charging system warning light
or the temperature warning light, fluid leaks, strange odors, smoke or
loss of engine power, could indicate that the emission control system is
not working properly.

Exhaust leaks may result in entry of harmful and potentially
lethal fumes into the passenger compartment.

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