2021 FORD Mustang Fuel and Refueling User Guide
2024 Ford Mustang Specs, Price, Features, Mileage (Brochure)
Fuel and Refueling
Some fuel stations, particularly those in high altitude areas, offer fuels posted as regular unleaded gasoline with an octane rating below 87. The use of these fuels could result in engine damage that will not be covered by the vehicle warranty. For best overall vehicle and engine performance, premium fuel with an octane rating of 91 or higher is recommended. Do not be concerned if the engine sometimes knocks lightly. However, if the engine knocks heavily while using fuel with the recommended octane rating, contact an authorized dealer to prevent any engine damage. We recommend Top Tier detergent gasolines, where available to help minimize engine deposits and maintain optimal vehicle and engine performance. For additional information, refer to www.toptiergas.com. Note: Use of any fuel for which the vehicle was not designed can impair the emission control system, cause loss of vehicle performance, and cause damage to the engine which may not be covered by the vehicle Warranty. Do not use:
- Diesel fuel.
- Fuels containing kerosene or paraffin.
- Fuel containing more than 15% ethanol or E85 fuel.
- Fuels containing methanol.
- Fuels containing metallic-based additives, including manganese-based compounds.
- Fuels containing the octane booster additive, methylcyclopentadienyl manganese tricarbonyl (MMT).
- Leaded fuel, using leaded fuel is prohibited by law.
The use of fuels with metallic compounds such as methylcyclopentadienyl manganese tricarbonyl (commonly known as MMT), which is a manganese-based fuel additive, will impair engine performance and affect the emission control system.
FUEL QUALITY
Choosing the Right Fuel 
Your vehicle is designed to operate on regular unleaded gasoline with a minimum pump (R+M)/2 octane rating of 87. Some fuel stations, particularly those in high altitude areas, offer fuels posted as regular unleaded gasoline with an octane rating below 87. The use of these fuels could result in engine damage that will not be covered by the vehicle warranty. For best overall vehicle and engine performance, premium fuel with an octane rating of 91 or higher is recommended. Do not be concerned if the engine sometimes knocks lightly. However, if the engine knocks heavily while using fuel with the recommended octane rating, contact an authorized dealer to prevent any engine damage. We recommend Top Tier detergent gasolines, where available to help minimize engine deposits and maintain optimal vehicle and engine performance. For additional information, refer to www.toptiergas.com.
Note: Use of any fuel for which the vehicle was not designed can impair the emission control system, cause loss of vehicle performance, and cause damage to the engine which may not be covered by the vehicle Warranty. Do not use:
- Diesel fuel.
- Fuels containing kerosene or paraffin.
- Fuel containing more than 15% ethanol or E85 fuel.
- Fuels containing methanol.
- Fuels containing metallic-based additives, including manganese-based compounds.
- Fuels containing the octane booster additive, methylcyclopentadienyl manganese tricarbonyl (MMT).
- Leaded fuel, using leaded fuel is prohibited by law.
The use of fuels with metallic compounds such as methylcyclopentadienyl manganese tricarbonyl (commonly known as MMT), which is a manganese-based fuel additive, will impair engine performance and affect the emission control system.
FUEL QUALITY
Choosing the Right Fuel Your vehicle is designed to operate on regular unleaded gasoline with a minimum pump (R+M)/2 octane rating of 87. Some fuel stations, particularly those in high altitude areas, offer fuels posted as regular unleaded gasoline with an octane rating below 87. The use of these fuels could result in engine damage that will not be covered by the vehicle warranty. For best overall vehicle and engine performance, premium fuel with an octane rating of 91 or higher is recommended. The performance gained by using premium fuel is most noticeable in hot weather as well as other conditions, for example when towing a trailer. Do not be concerned if the engine sometimes knocks lightly. However, if the engine knocks heavily while using fuel with the recommended octane rating, contact an authorized dealer to prevent any engine damage. We recommend Top Tier detergent gasolines, where available to help minimize engine deposits and maintain optimal vehicle and engine performance. For additional information, refer to www.toptiergas.com.
Note: Use of any fuel for which the vehicle was not designed can impair the emission control system, cause loss of vehicle performance, and cause damage to the engine which may not be covered by the vehicle Warranty. Do not use:
- Diesel fuel.
- Fuels containing kerosene or paraffin.
- Fuel containing more than 15% ethanol or E85 fuel.
- Fuels containing methanol.
- Fuels containing metallic-based additives, including manganese-based compounds.
- Fuels containing the octane booster additive, methylcyclopentadienyl manganese tricarbonyl (MMT). Leaded fuel, using leaded fuel is prohibited by law.
- The use of fuels with metallic compounds such as methylcyclopentadienyl manganese tricarbonyl (commonly known as MMT), which is a manganese-based fuel additive, will impair engine performance and affect the emission control system.
FUEL FILLER FUNNEL LOCATION The fuel filler funnel is under the luggage compartment floor covering.
RUNNING OUT OF FUEL Running out of fuel can cause damage not covered by the vehicle Warranty. If your vehicle runs out of fuel:
- Add a minimum of 1.3 gal (5 L) of fuel to restart the engine.
- You may need to switch 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. When restarting, cranking time takes a few seconds longer than normal.
Note: If your vehicle is on a steep slope, more fuel may be required. Filling a Portable Fuel Container WARNING: Flow of fuel through a fuel pump nozzle can produce static electricity. This can cause a fire if you are filling an ungrounded fuel container. Use the following guidelines to avoid electrostatic charge build-up, which can produce a spark, when filling an ungrounded fuel container:
- Only use an approved fuel container to transfer fuel to your vehicle. Place the container on the ground when filling it.
- Do not fill a fuel container when it is inside your vehicle (including the cargo area).
- Keep the fuel pump nozzle in contact with the fuel container when filling it.
- Do not use a device that holds the fuel pump nozzle lever in the fill position.
Adding Fuel From a Portable Fuel Container WARNING: Do not insert the nozzle of a fuel container or an aftermarket funnel into the fuel filler neck. This may damage the fuel system filler neck or its seal and cause fuel to run onto the ground.
WARNING: Do not try to pry open or push open the capless fuel system with foreign objects. This could damage the fuel system and its seal and cause injury to you or others.
WARNING: Do not dispose of fuel in the household refuse or the public sewage system. Use an authorized waste disposal facility. When refueling the vehicle fuel tank from a fuel container, use the fuel filler funnel included with your vehicle. See Fuel Filler Funnel Location (page 154). Note: Do not use aftermarket funnels as they may not work with the capless fuel system and can damage it. When refueling the vehicle fuel tank from a fuel container, do the following:
- Fully open the fuel filler door.
- Fully insert the fuel filler funnel into the fuel filler inlet.
- Add fuel to your vehicle from the fuel container.
- Remove the fuel filler funnel.
- Fully close the fuel filler door.
- Clean the fuel filler funnel and place it back in your vehicle or correctly dispose of it.
Note: Extra funnels can be purchased from an authorized dealer if you choose to dispose of the funnel.
REFUELING
Refueling System Overview 
- A Fuel filler door.
- B Fuel tank filler valve.
- C Fuel tank filler pipe.
Your vehicle does not have a fuel tank filler cap. 
- Left-hand side. To open the fuel filler door, press the center rear edge of the fuel filler door and then release.
- Right-hand side. To open the fuel filler door, press the center rear edge of the fuel filler door and then release.
- Left-hand side. Pull the rear of the fuel filler door to open it.
- Right-hand side. Pull the rear of the fuel filler door to open it.
Refueling Your Vehicle WARNING: When refueling always shut the engine off and never allow sparks or open flames near the fuel tank filler valve. Never smoke or use a cell phone while refueling. Fuel vapor is extremely hazardous under certain conditions. Avoid inhaling excess fumes.
WARNING: The fuel system may be under pressure. If you hear a hissing sound near the fuel filler inlet, do not refuel until the sound stops. Otherwise, fuel may spray out, which could cause serious personal injury.
WARNING: Do not pry open the fuel tank filler valve. This could damage the fuel system. Failure to follow this instruction could result in fire, personal injury or death.
WARNING: Do not remove the fuel pump nozzle from its fully inserted position when refueling.
WARNING: Stop refueling when the fuel pump nozzle automatically shuts off for the first time. Failure to follow this will fill the expansion space in the fuel tank and could lead to fuel overflowing.
WARNING: Do not overfill the fuel tank. The pressure in an overfilled tank may cause leakage and lead to fuel spray and fire. WARNING: Wait at least five seconds before removing the fuel pump nozzle to allow any residual fuel to drain into the fuel tank.
- Fully open the fuel filler door.
- Select the correct fuel pump nozzle for your vehicle.
- Insert the fuel pump nozzle up to the first notch on the nozzle A. Keep the fuel pump nozzle resting on the fuel tank filler pipe.
- Hold the fuel pump nozzle in position B when refueling. Holding the fuel pump nozzle in position A can affect the flow of fuel and shut off the fuel pump nozzle before the fuel tank is full.
- Operate the fuel pump nozzle within the area shown.
- When you finish refueling slightly raise the fuel pump nozzle and slowly remove it.
- Fully close the fuel filler door.
Do not attempt to start the engine if you have filled the fuel tank with incorrect fuel. Incorrect fuel use could cause damage not covered by the vehicle Warranty. Have your vehicle immediately checked. Refueling System Warning If the fuel tank filler valve does not fully close, a message could appear in the information display.
| Message |
| Check Fuel Fill Inlet |
If the message appears, do the following:
- Stop your vehicle as soon as it is safe to do so and switch the engine off.
- Shift into park (P) or neutral (N).
- Apply the parking brake.
- Fully open the fuel filler door.
- Check the fuel tank filler valve for any debris that may be restricting its movement.
- Remove any debris from the fuel tank filler valve.
- Fully insert a fuel pump nozzle or the fuel filler funnel provided with your vehicle into the fuel filler pipe. See Fuel Filler Funnel Location (page 154). This action should dislodge any debris that may be preventing the fuel tank filler valve from fully closing.
- Remove the fuel pump nozzle or fuel filler funnel from the fuel filler pipe.
- Fully close the fuel filler door.
Note: The message may not immediately reset. If the message continues to appear and a warning lamp illuminates, have your vehicle checked as soon as possible.
FUEL CONSUMPTION
Advertised Capacity The advertised capacity is the maximum amount of fuel that you can add to the fuel tank after running out of fuel. Included in the advertised capacity is an empty reserve. The empty reserve is an unspecified amount of fuel that remains in the fuel tank when the fuel gauge indicates empty. Note: The amount of fuel in the empty reserve varies and should not be relied upon to increase driving range.
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.
- se 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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2024 Ford Mustang Specs, Price, Features, Mileage (Brochure)