
which equates to a freeze point of -34°F (-36°C). Coolant concentration
testing is possible with a hydrometer or antifreeze tester. The level of
coolant should be maintained at the FULL COLD level or within the
COLD FILL RANGE in the coolant reservoir. If the level falls below, add
coolant per the instructions in theAdding engine coolantsection.
Your vehicle was factory-filled with a 50/50 engine coolant and water
concentration. If the concentration of coolant falls below 40% or above
60%, the engine parts could become damaged or not work properly.A
50/50 mixture of coolant and water provides the following:
•Freeze protection down to -34°F (-36°C).
•Boiling protection up to 265°F (129°C).
•Protection against rust and other forms of corrosion.
•Proper function of calibrated gauges.
When the engine is cold, check the
level of the engine coolant in the
reservoir.
•The engine coolant should be at the FULL COLD level or within the
COLD FILL RANGE as listed on the engine coolant reservoir
(depending upon application).
•Refer toscheduled maintenance informationfor service interval
schedules.
•Be sure to read and understandPrecautions when servicing your
vehiclein this chapter.
If the engine coolant has not been checked at the recommended interval,
the engine coolant reservoir may become low or empty. If the reservoir is
low or empty, add engine coolant to the reservoir. Refer toAdding
engine coolantin this chapter.
Note:Automotive fluids are not interchangeable; do not use engine
coolant, antifreeze or windshield washer fluid outside of its specified
function and vehicle location.
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Adding engine coolant
When adding coolant, make sure it is a 50/50 mixture of engine coolant
and distilled water. Add the mixture to the coolant reservoir,when the
engine is cool,until the appropriate fill level is obtained.
WARNING:Do not add engine coolant when the engine is hot.
Steam and scalding liquids released from a hot cooling system
can burn you badly. Also, you can be burned if you spill coolant on hot
engine parts.
WARNING:Do not put engine coolant in the windshield washer
fluid container. If sprayed on the windshield, engine coolant
could make it difficult to see through the windshield.
•Do not mix coolants. Add the coolant type originally equipped
in your vehicle.Refer toMaintenance product specifications and
capacitiesin this chapter.
Note:Do not use stop leak pellets or cooling system sealants/additives
as they can cause damage to the engine cooling and/or heating systems.
This damage would not be covered under your vehicle’s warranty.
•A large amount of water without engine coolant may be added, in case
of emergency, to reach a vehicle service location. In this instance, the
cooling system must be drained and refilled with a 50/50 mixture of
engine coolant and distilled water as soon as possible. Water alone
(without engine coolant) can cause engine damage from corrosion,
overheating or freezing.
•Do not use alcohol, methanol, brine or any engine coolants
mixed with alcohol or methanol antifreeze (coolant).Alcohol
and other liquids can cause engine damage from overheating or
freezing.
•Do not add extra inhibitors or additives to the coolant.These
can be harmful and compromise the corrosion protection of the engine
coolant.
For vehicles with overflow coolant systems with a non-pressurized cap
on the coolant recovery system, add coolant to the coolant recovery
reservoir when the engine is cool. Add the proper mixture of coolant and
water to the FULL COLD level. For all other vehicles which have a
coolant degas system with a pressurized cap, or if it is necessary to
remove the coolant pressure relief cap on the radiator of a vehicle with
an overflow system, follow these steps to add engine coolant.
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What you should know about fail-safe cooling (if equipped)
If the engine coolant supply is depleted, this feature allows the vehicle to
be driven temporarily before incremental component damage is incurred.
The “fail-safe” distance depends on ambient temperatures, vehicle load
and terrain.
How fail-safe cooling works
If the engine begins to overheat:
•The engine coolant temperature gauge will move to the red (hot)
area.
•The coolant temperature warning light
will illuminate.
•The service engine soon
indicator will illuminate.
If the engine reaches a preset over-temperature condition, the engine
will automatically switch to alternating cylinder operation. Each disabled
cylinder acts as an air pump and cools the engine.
When this occurs the vehicle will still operate. However:
•The engine power will be limited.
•The air conditioning system will be disabled.
Continued operation will increase the engine temperature and the engine
will completely shut down, causing steering and braking effort to
increase.
Once the engine temperature cools, the engine can be re-started. Take
your vehicle to a service facility as soon as possible to minimize engine
damage.
When fail-safe mode is activated
You have limited engine power when in the fail-safe mode, so drive the
vehicle with caution. The vehicle will not be able to maintain high-speed
operation and the engine will run rough. Remember that the engine is
capable of completely shutting down automatically to prevent engine
damage, therefore:
1. Pull off the road as soon as safely possible and turn off the engine.
2. Arrange for the vehicle to be taken to a service facility.
3. If this is not possible, wait a short period for the engine to cool.
4. Check the coolant level and replenish if low.
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WARNING:Never remove the coolant reservoir cap while the
engine is running or hot.
5. Re-start the engine and take your vehicle to a service facility.
Driving the vehicle without repairing the engine problem
increases the chance of engine damage. Take your vehicle to a
service facility as soon as possible.
FUEL FILTER
Your vehicle is equipped with a lifetime fuel filter that is integrated with
the fuel tank. Regular maintenance or replacement is not needed.
WHAT YOU SHOULD KNOW ABOUT AUTOMOTIVE FUELS
Important safety precautions
WARNING:Do not overfill the fuel tank. The pressure in an
overfilled tank may cause leakage and lead to fuel spray and fire.
WARNING:The fuel system may be under pressure. If you hear
a hissing sound near the fuel filler door (Easy Fuel™ “no cap”
fuel system), do not refuel until the sound stops. Otherwise, fuel may
spray out, which could cause serious personal injury.
WARNING:Automotive fuels can cause serious injury or death
if misused or mishandled.
WARNING:Gasoline may contain benzene, which is a
cancer-causing agent.
Observe the following guidelines when handling automotive fuel:
•Extinguish all smoking materials
and any open flames before
refueling your vehicle.
•Always turn off the vehicle before
refueling.
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Note:A fuel spillage concern may occur if overfilling the fuel tank. Do
not overfill the tank to the point that the fuel is able to bypass the fuel
filler nozzle. The overfilled fuel may run down the drain located within
the fuel filler housing and to the ground.
If the Check Fuel Fill Inlet message comes on, the fuel fill inlet may not
have properly closed. The inlet may have stuck open or debris may be
preventing the inlet from fully closing. At the next opportunity, safely
pull off the road, turn off the engine, open the fuel filler door and
remove any visible debris from the fuel fill opening. Insert either the fuel
fill nozzle or the fuel fill funnel (seeRefilling with a portable fuel
containerfor funnel location) provided with the vehicle several times to
dislodge any debris and/or allow the inlet to close properly. If this action
corrects the problem, the Check Fuel Fill Inlet message may not reset
immediately. It may take several driving cycles for the Check Fuel Fill
Inlet message to turn off. A driving cycle consists of an engine start-up
(after four or more hours with the engine off) followed by city/highway
driving. Continuing to drive with the Check Fuel Fill Inlet message on
may cause the service engine soon lamp to turn on as well.
WARNING:The fuel system may be under pressure. If you hear
a hissing sound near the fuel filler door (Easy Fuel™ “no cap”
fuel system), do not refuel until the sound stops. Otherwise, fuel may
spray out, which could cause serious personal injury.
Choosing the right fuel
Use only UNLEADED fuel or UNLEADED fuel blended with a maximum
of 10% ethanol. Do not use fuel ethanol (E85), diesel, methanol, leaded
fuel or any other 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.
Note:Use of any fuel other than those recommended may cause
powertrain damage, a loss of vehicle performance, and repairs may not
be covered under warranty.
Octane recommendations
3.7L V6 engine
Your vehicle will run normally on 87 octane regular fuel. Premium fuel
will provide improved performance.
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3.5L V6 EcoBoost engine
Your vehicle is designed to run on regular fuel with an octane rating of
87 or higher. For best overall performance, premium fuel with an octane
rating of 91 or higher is recommended. The performance gained by using
premium fuel will be most noticeable in hot weather or in severe duty
applications such as towing a trailer.
Some stations offer fuels posted as
Regularwith an octane rating
below 87, particularly in high
altitude areas. Fuels with octane
levels below 87 are not
recommended for either engine. Do not be concerned if your engine
sometimes knocks lightly. However, if it knocks heavily while you are
using fuel with the recommended octane rating, see your authorized
dealer 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. 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.
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
effect on powertrain components.
87(R+M)/2 METHOD
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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. On restarting, cranking time will take a few seconds longer
than normal.
•Normally, adding 1 gallon (3.8L) of fuel is enough to restart the
engine. If the vehicle is out of fuel and on a steep grade, more than
1 gallon (3.8L) may be required.
•The service engine soon
indicator may come on. For more
information on the service engine soon indicator, refer toWarning
lights and chimesin theInstrument Clusterchapter.
Refilling with a portable fuel container
With the Easy Fuel™ “no cap” fuel system, use the following directions
when filling from a portable fuel container:
WARNING:Do not insert the nozzle of portable fuel containers
or aftermarket funnels into the Easy Fuel™ system. This could
damage the fuel system and its seal, and may cause fuel to run onto
the ground instead of filling the tank, which could result in serious
personal injury.
WARNING:Do not try to pry open or push open the Easy
Fuel™ system with foreign objects. This could damage the fuel
system and its seal and cause injury to you or others.
When filling the vehicle’s fuel tank from a portable fuel container, use the
funnel included with the vehicle.
1. After lifting the trunk cargo
cover, locate the white plastic
funnel. It is attached to the rear,
lower edge of the spare tire
compartment.
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![LINCOLN MKS 2010 Owners Manual •Carrying unnecessary weight may reduce fuel economy (approximately
1 mpg [0.4 km/L] is lost for every 400 lb [180 kg] of weight carried).
•Adding certain accessories to your vehicle (for example LINCOLN MKS 2010 Owners Manual •Carrying unnecessary weight may reduce fuel economy (approximately
1 mpg [0.4 km/L] is lost for every 400 lb [180 kg] of weight carried).
•Adding certain accessories to your vehicle (for example](/manual-img/15/6908/w960_6908-330.png)
•Carrying unnecessary weight may reduce fuel economy (approximately
1 mpg [0.4 km/L] is lost for every 400 lb [180 kg] of weight carried).
•Adding certain accessories to your vehicle (for example bug
deflectors, rollbars/light bars, running boards, ski racks) may reduce
fuel economy.
•Using fuel blended with alcohol may lower fuel economy.
•Fuel economy may decrease with lower temperatures during the first
8–10 miles (12–16 km) 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.
•Close windows for high speed driving.
EPA fuel economy estimates
Every new vehicle should have a sticker on the window called the
Monroney Label which contains EPA fuel economy estimates. Contact
your authorized dealer if the Monroney Label is not supplied with your
vehicle. The EPA fuel economy estimates should be your guide for the
fuel economy comparisons with other vehicles. 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 inscheduled maintenance information
performed according to the specified schedule.
The scheduled maintenance items listed inscheduled maintenance
informationare 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
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