2003 FORD MUSTANG Owners Manual

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.
Do not use fuel containing methanol. It can damage
critical fuel system components.
Your vehicle was not designed to use fuel or fuel
additives with metallic compounds, including
manganese-based compounds containing MMT.
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.
87(R+M)/2 METHOD
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Fuelquality
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.
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 issued 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. In
Canada, look for fuels that display theAuto
Makers’Choice
logo.
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:
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•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 theInstrument 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 theRefill capacitiessection 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
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219

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.
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220

4. Subtract your initial odometer reading from the
current odometer reading.
5. Follow one of the simple calculations in order to
determine fuel economy:
Multiply liters used by 100, then divide by
total kilometers traveled.
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.
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221

•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 third
and fourth gear occurs. Unnecessary shifting of
this type could result in reduced fuel economy.
•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 toLubricant
specificationsin 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.
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•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.
•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.
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
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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“Service Engine Soon”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.
Do not make any unauthorized changes to your
vehicle or engine. By law, vehicle owners and anyone
who manufactures, repairs, services, sells, leases,
trades vehicles, or supervises a fleet of vehicles are
not permitted to intentionally remove an emission
control device or prevent it from working.
Information about your vehicle’s emission system is
on the Vehicle Emission Control Information Decal
located on or near the engine. This decal identifies
engine displacement and gives some tune up
specifications.
Please consult yourWarranty Guidefor complete
emission warranty information.
Readiness for Inspection/Maintenance (I/M)
testing
In some localities, it may be a legal requirement to
pass an I/M test of the on-board diagnostics system.
If your“Check Engine/Service Engine Soon”light is
on, refer to the description in theWarning lights
and chimessection of theInstrument cluster
chapter. Your vehicle may not pass the I/M test with
the“Check Engine/Service Engine Soon”light on.
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224