2021 FORD MUSTANG Fuel

Filling the Fuel Tank
For consistent results when refueling:
•
Switch the ignition off before fueling,
an inaccurate reading results if you
leave the engine running.
• Use the same fill rate,
low-medium-high, each time you fill
the tank.
• Allow no more than one automatic
shut-off when refueling.
Results are most accurate when the filling
method is consistent.
Calculating Fuel Economy
Your vehicle calculates fuel economy
figures through the trip computer average
fuel function. See Information Displays
(page 99).
The first
1,000 mi (1,600 km) of driving is
the break-in period of the engine. The
system obtains a more accurate
measurement after
2,000– 3,000 mi
(3,200–4,800 km).
Keep a record for at least one month and
record the type of driving, for example city
or highway. This provides an accurate
estimate of your vehicle ’s fuel economy
under current driving conditions. Keeping
records during summer and winter shows
how temperature impacts fuel economy.
Conditions Affecting Fuel Efficiency
• Carrying unnecessary weight in your
vehicle may reduce fuel economy.
• Avoid adding accessories that increase
aerodynamic drag to your vehicle such
as bug deflectors, car top carriers and
ski or bike racks.
• Remove empty roof racks and keep
windows shut at high speeds to reduce
wind resistance and fuel use. •
Check and adjust tire pressure
regularly. Underinflated tires increases
fuel consumption.
• Sudden acceleration and braking
degrade fuel efficiency. Drive smoothly
looking as far ahead as possible and
avoid short trips when possible.
• Fuel efficiency degrades with lower
temperatures.
• Comfort features use additional energy
and consume more fuel. Use AC and
other comfort features only when
necessary.
• Using fuel blended with alcohol may
increase fuel consumption.
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Mustang (CZG) Canada/United States of America, Vehicles Built From: 14-09-2020, enUSA, Edition date: 202010, Second-Printing Fuel and Refueling

EMISSION LAW
WARNING: Do not remove or alter
the original equipment floor covering or
insulation between it and the metal floor
of the vehicle. The floor covering and
insulation protect occupants of the
vehicle from the engine and exhaust
system heat and noise. On vehicles with
no original equipment floor covering
insulation, do not carry passengers in a
manner that permits prolonged skin
contact with the metal floor. Failure to
follow these instructions may result in
fire or personal injury.
U.S. federal laws and certain state laws
prohibit removing or rendering inoperative
emission control system components.
Similar federal or provincial laws may
apply in Canada. We do not approve of any
vehicle modification without first
determining applicable laws. Tampering with emissions
control systems including
related sensors can result in
reduced engine power and the illumination
of the service engine soon light.
Tampering With a Noise Control
System
Federal laws prohibit the following acts:
• Removal or rendering inoperative by
any person other than for purposes of
maintenance.
• Repair or replacement of any device or
element of the design incorporated into
a new vehicle for the purpose of noise
control prior to its sale or delivery to
the ultimate purchaser or while it is in
use.
• The use of the vehicle after any person
removes or renders inoperative any
device or element of the design. The U.S. Environmental Protection Agency
may presume to constitute tampering as
follows:
•
Removal of hood blanket, fender apron
absorbers, fender apron barriers,
underbody noise shields or acoustically
absorptive material.
• Tampering or rendering inoperative the
engine speed governor, to allow engine
speed to exceed manufacturer
specifications.
If the engine does not start, runs rough,
experiences a decrease in engine
performance, experiences excess fuel
consumption or produces excessive
exhaust smoke, check for the following:
• A plugged or disconnected air inlet
system hose.
• A plugged engine air filter element.
• A clogged fuel filter.
• Contaminated fuel.
• Air in the fuel system, due to loose
connections.
• Fuel system leaks, due to loose
connections.
• An open or pinched sensor hose.
• Incorrect engine oil level.
• Incorrect fuel for climatic conditions.
• Incorrect engine oil viscosity for
climactic conditions.
Note: Some vehicles have a lifetime fuel
filter that is integrated with the fuel tank.
Regular maintenance or replacement is not
needed.
Note: If these checks do not help you
correct the concern, see your authorized
dealer as soon as possible.
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Mustang (CZG) Canada/United States of America, Vehicles Built From: 14-09-2020, enUSA, Edition date: 202010, Second-Printing Engine Emission Control

CATALYTIC CONVERTER
WARNING: Do not park, idle or
drive your vehicle on dry grass or other
dry ground cover. The emission system
heats up the engine compartment and
exhaust system, creating the risk of fire. WARNING:
The normal operating
temperature of the exhaust system is
very high. Never work around or attempt
to repair any part of the exhaust system
until it has cooled. Use special care when
working around the catalytic converter.
The catalytic converter heats up to a very
high temperature after only a short
period of engine operation and stays hot
after the engine is switched off. WARNING:
Exhaust leaks may
result in entry of harmful and potentially
lethal fumes into the passenger
compartment. If you smell exhaust
fumes inside your vehicle, have your
vehicle inspected immediately. Do not
drive if you smell exhaust fumes.
Your vehicle has various emission control
components and a catalytic converter that
enables it to comply with applicable
exhaust emission standards.
To make sure that the catalytic converter
and other emission control components
continue to work properly:
• Do not crank the engine for more than
10 seconds at a time.
• Do not run the engine with a spark plug
lead disconnected.
• Do not push-start or tow-start your
vehicle. Use booster cables. See Jump
Starting the Vehicle
(page 234).
• Use only the specified fuel listed.
• Do not switch the ignition off when your
vehicle is moving. •
Avoid running out of fuel.
• Have the items listed in scheduled
maintenance information performed
according to the specified schedule.
Note: Resulting component damage may
not be covered by the vehicle Warranty.
The scheduled maintenance items listed
in scheduled maintenance information are
essential to the life and performance of
your vehicle and to its emissions system.
If you use anything other than Ford,
Motorcraft or Ford-authorized parts 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.
Illumination of the service engine soon
indicator, 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.
An improperly operating or damaged
exhaust system may allow exhaust to
enter the vehicle. Have a damaged or
improperly operating exhaust system
inspected and repaired immediately.
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
also lists engine displacement.
Please consult your warranty information
for complete details.
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Mustang (CZG) Canada/United States of America, Vehicles Built From: 14-09-2020, enUSA, Edition date: 202010, Second-Printing Engine Emission Control

On-Board Diagnostics (OBD-II)
Your vehicle has a computer known as the
on-board diagnostics system (OBD-II) that
monitors the engine
’s emission control
system. The system protects the
environment by making sure that your
vehicle continues to meet government
emission standards. The OBD-II system
also assists a service technician in properly
servicing your vehicle. When the service engine soon
indicator illuminates, the OBD-II
system has detected a
malfunction. Temporary malfunctions may
cause the service engine soon indicator to
illuminate. Examples are:
1. Your vehicle has run out of fuel —the
engine may misfire or run poorly.
2. Poor fuel quality or water in the fuel —the engine may misfire or run
poorly.
3. The fuel fill inlet may not have closed properly. See Refueling (page 156).
4. Driving through deep water —the
electrical system may be wet.
You can correct these temporary
malfunctions by filling the fuel tank with
good quality fuel, properly closing the fuel
fill inlet or letting the electrical system dry
out. After three driving cycles without these
or any other temporary malfunctions
present, the service engine soon indicator
should stay off the next time you start the
engine. A driving cycle consists of a cold
engine startup followed by mixed city and
highway driving. No additional vehicle
service is required. If the service engine soon indicator remains
on, have your vehicle serviced at the first
available opportunity. Although some
malfunctions detected by the OBD-II may
not have symptoms that are apparent,
continued driving with the service engine
soon indicator on can result in increased
emissions, lower fuel economy, reduced
engine and transmission smoothness and
lead to more costly repairs.
Readiness for Inspection and
Maintenance (I/M) Testing
Some state and provincial and local
governments may have
Inspection/Maintenance (I/M) programs
to inspect the emission control equipment
on your vehicle. Failure to pass this
inspection could prevent you from getting
a vehicle registration.
If the service engine soon
indicator is on or the bulb does
not work, your vehicle may need
service. See On-Board Diagnostics.
Your vehicle may not pass the I/M test if
the service engine soon indicator is on or
not working properly (bulb is burned out),
or if the OBD-II system has determined
that some of the emission control systems
have not been properly checked. In this
case, the vehicle is not ready for I/M
testing.
If the vehicle ’s engine or transmission has
just been serviced, or the battery has
recently run down or been replaced, the
OBD-II system may indicate that the
vehicle is not ready for I/M testing. To
determine if the vehicle is ready for I/M
testing, turn the ignition key to the on
position for 15 seconds without cranking
the engine. If the service engine soon
indicator blinks eight times, it means that
the vehicle is not ready for I/M testing; if
the service engine soon indicator stays on
solid, it means that your vehicle is ready
for I/M testing.
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Mustang (CZG) Canada/United States of America, Vehicles Built From: 14-09-2020, enUSA, Edition date: 202010, Second-Printing Engine Emission Control

MANUAL TRANSMISSION
Using the Clutch
Note:
Failure to fully press the clutch pedal
to the floor may cause increased shift
efforts, prematurely wear transmission
components or damage the transmission.
Note: Do not drive with your foot resting
on the clutch pedal or use the clutch pedal
to hold your vehicle at a standstill while
waiting on a hill. These actions reduces the
life of the clutch and could nullify a clutch
warranty claim.
Note: The engine may not start unless the
intelligent access key is inside your vehicle. Manual transmission vehicles have a
starter interlock that prevents cranking the
engine unless you fully press the clutch
pedal.
To start the vehicle:
1.
Make sure the parking brake is fully set.
2. Press the clutch pedal to the floor, then
put the gearshift lever in the neutral
(N) position.
3. Start the engine.
4. Press the brake pedal and move the gearshift lever to the desired gear; first
(1) or reverse (R). 5.
Release the parking brake, then slowly
release the clutch pedal while slowly
pressing on the accelerator.
During each shift, fully press the clutch
pedal to the floor. Make sure to properly
position the floor mat so it does not
interfere with the full extension of the
clutch pedal.
Recommended Shift Speeds
Note: Do not downshift into first (1) when
your vehicle is moving faster than 15 mph
(24 km/h). This damages the clutch.
2.3L Upshifts When Accelerating - Recom-
mended for Best Fuel Economy
Shift from:15 mph (24 km/h)
1 - 2
24 mph (39 km/h)
2 - 3
35 mph (56 km/h)
3 - 4
41 mph (66 km/h)
4 - 5
50 mph (80 km/h)
5 - 6
5.0L Upshifts When Accelerating - Recom-
mended for Best Fuel Economy
Shift from:14 mph (23 km/h)
1 - 2
25 mph (40 km/h)
2 - 3
35 mph (56 km/h)
3 - 4
41 mph (66 km/h)
4 - 5
48 mph (77 km/h)
5 - 6
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Mustang (CZG) Canada/United States of America, Vehicles Built From: 14-09-2020, enUSA, Edition date: 202010, Second-Printing TransmissionE144954

Understanding the Positions of
Your Automatic Transmission
Putting your vehicle in gear:
1. Fully press down on the brake pedal.
2. Press and hold the button on the top
of the gearshift lever.
3. Move the gearshift lever into the desired gear.
4. Release the button and your transmission remains in the selected
gear. Transmission Selector Positions
The instrument cluster displays the current
gear.
Park (P)
This position locks the transmission and
prevents the rear wheels from turning.
Come to a complete stop before putting
your vehicle into and out of park (P).
Reverse (R)
With the selector in reverse (R), your
vehicle moves backward. Always come to
a complete stop before shifting into and
out of reverse (R). Neutral (N)
With the selector in neutral (N), you can
start your vehicle and it is free to roll. Hold
the brake pedal down when in this position.
Drive (D)
Drive (D) is the normal driving position for
the best fuel economy. The overdrive
function allows automatic upshifts and
downshifts through all gears.
Sport (S)
Putting your vehicle in sport (S):
•
Provides additional engine braking and
extends lower gear operation to
enhance performance for uphill climbs,
hilly terrain or mountainous areas. This
increases engine RPM during engine
braking.
• Provides additional lower gear
operation through the automatic
transmission shift strategy.
• Provides gear upshifts and downshifts
more quickly at higher engine speeds.
SelectShift Automatic ™
Transmission (If Equipped)
This feature gives you the ability to change
gears up or down as desired.
As long as the engine speed does not
exceed the maximum allowable limit, you
can downshift the vehicle. SelectShift
automatically downshifts at low engine
speeds in order to prevent engine stalls.
Note: Engine damage may occur if you
maintain excessive engine revving without
shifting.
In drive (D) mode, SelectShift
automatically upshifts at the optimal max
engine speed, regardless of accelerator
pedal travel.
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Mustang (CZG) Canada/United States of America, Vehicles Built From: 14-09-2020, enUSA, Edition date: 202010, Second-Printing TransmissionE174572

When Towing a Trailer
•
Do not drive faster than 70 mph
(113 km/h) during the first 500 mi
(800 km).
• Do not make full-throttle starts.
• Check your hitch, electrical connections
and trailer wheel lug nuts thoroughly
after you have traveled 50 mi (80 km).
• When stopped in congested or heavy
traffic during hot weather, place the
transmission in park (P) or neutral (N)
to aid engine and transmission cooling
and to help air conditioning
performance.
• Switch off the speed control with
heavy loads or in hilly terrain. The
speed control may turn off
automatically when you are towing on
long, steep grades.
• Shift to a lower gear when driving down
a long or steep hill. Do not apply the
brakes continuously, as they may
overheat and become less effective.
• If your transmission is equipped with a
Grade Assist or Tow/Haul feature, use
this feature when towing. This provides
engine braking and helps eliminate
excessive transmission shifting for
optimum fuel economy and
transmission cooling.
• Allow more distance for stopping with
a trailer attached. Anticipate stops and
brake gradually.
• Avoid parking on a slope. However, if
you must park on a slope:
1. Turn the steering wheel to point your vehicle tires away from traffic flow.
2. Set your vehicle parking brake.
3. Place the automatic transmission in park (P) or manual transmission in a
low gear. 4. Place wheel chocks in front and back
of the trailer wheels. Chocks are not
included with your vehicle.
Launching or Retrieving a Boat or
Personal Watercraft (PWC)
Note: Disconnect the wiring to the trailer
before
backing the trailer into the water.
Note: Reconnect the wiring to the trailer
after
removing the trailer from the water.
When backing down a ramp during boat
launching or retrieval:
• Do not allow the static water level to
rise above the bottom edge of the rear
bumper.
• Do not allow waves to break higher
than
6 in (15 cm) above the bottom
edge of the rear bumper.
Exceeding these limits may allow water to
enter vehicle components:
• Causing internal damage to the
components.
• Affecting driveability, emissions, and
reliability.
Any time the rear axle submerges in water,
replace the rear axle lubricant. Water may
contaminate the rear axle lubricant, which
is not a normal maintenance inspection
item unless there is a possibility of a leak
or other axle repair is required.
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Mustang (CZG) Canada/United States of America, Vehicles Built From: 14-09-2020, enUSA, Edition date: 202010, Second-Printing Towing

REDUCED ENGINE
PERFORMANCE
WARNING: If you continue to drive
your vehicle when the engine is
overheating, the engine could stop
without warning. Failure to follow this
instruction could result in the loss of
control of your vehicle.
If the engine coolant temperature gauge
needle moves to the upper limit position,
the engine is overheating. See Gauges
(page 90).
You must only drive your vehicle for a short
distance if the engine overheats. The
distance you can travel depends on
ambient temperature, vehicle load and
terrain. The engine continues to operate
with limited power for a short period of
time.
If the engine temperature continues to rise,
the fuel supply to the engine reduces. The
air conditioning switches off and the engine
cooling fan operates continually.
1. Gradually reduce your speed and stop your vehicle as soon as it is safe to do
so.
2. Immediately switch the engine off to prevent severe engine damage.
3. Wait for the engine to cool down.
4. Check the coolant level. See
Engine
Coolant Check (page 264).
5. Have your vehicle checked as soon as possible. Reduced Vehicle Top Speed
Your vehicle's ability to reach and maintain
top speed is partially dependent upon
ambient temperature. Under certain
environmental conditions, your vehicle's
top speed may be reduced to protect
powertrain components.
ECONOMICAL DRIVING
Fuel economy is affected by several things
such as how you drive, the conditions you
drive under and how you maintain your
vehicle.
There are some things to keep in mind that
may improve your fuel economy:
•
Accelerate and slow down in a smooth,
moderate fashion.
• Drive at steady speeds.
• Anticipate stops; slowing down may
eliminate the need to stop.
• Combine errands and minimize
stop-and-go driving (When running
errands, go to the furthest destination
first and then work your way back
home).
• Close the windows for high-speed
driving.
• Drive at reasonable speeds.
• Keep the tires properly inflated and use
only the recommended size.
• Use the recommended engine oil.
• Perform all regularly scheduled
maintenance.
There are also some things you may want
to avoid doing because they reduce your
fuel economy:
• Avoid sudden or hard accelerations.
• Avoid revving the engine before turning
off the car.
• Avoid long idle periods.
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Mustang (CZG) Canada/United States of America, Vehicles Built From: 14-09-2020, enUSA, Edition date: 202010, Second-Printing Driving Hints