2021 LINCOLN NAUTILUS check engine

MAINTENANCE PRECAUTIONS
Service your vehicle regularly to help
maintain its roadworthiness and resale value.
There is a large network of authorized
dealers that are there to help you with their
professional servicing expertise. We believe
that their specially trained technicians are
best qualified to service your vehicle properly
and expertly. They are supported by a wide
range of highly specialized tools developed
specifically for servicing your vehicle.
If your vehicle requires professional service,
an authorized dealer can provide the
necessary parts and service. Check your
warranty information to find out which parts
and services are covered.
Use only recommended fuels, lubricants,
fluids and service parts conforming to
specifications. See Capacities and
Specifications (page 398).
• Do not work on a hot engine.
• Make sure that nothing gets caught in
moving parts. •
Do not work on a vehicle with the engine
running in an enclosed space, unless you
are sure you have enough ventilation.
• Keep all open flames and other burning
material, such as cigarettes, away from
the battery and all fuel related parts.
• Set the parking brake, shift the
transmission to park (P) and block the
wheels.
OPENING AND CLOSING THE
HOOD
Opening the Hood 1. Inside the vehicle, pull the hood release
handle located under the left-hand side
of the instrument panel. 2. Slightly lift the hood.
3. Release the hood latch by pushing the
secondary release lever to your left-hand
side.
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Engine coolant reservoir. See Checking the Coolant (page 340).
A
Engine oil dipstick.
See Engine Oil Dipstick Overview (page 338).
B
Engine oil filler cap.
See Adding Engine Oil (page 338).
C
Brake fluid reservoir.
See Checking the Brake Fluid (page 218).
D
Battery.
See Changing the 12V Battery (page 345).
E
Power distribution box.
See Accessing the Under Hood Fuse Box (page 316).
F
Air filter.
See Changing the Engine Air Filter (page 344).
G
Windshield washer fluid reservoir.
See Adding Washer Fluid (page 118).
H
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Engine coolant reservoir. See Checking the Coolant (page 340).
A
Brake fluid reservoir.
See Checking the Brake Fluid (page 218).
B
Battery.
See Changing the 12V Battery (page 345).
C
Power distribution box.
See Accessing the Under Hood Fuse Box (page 316).
D
Air filter assembly.
See Changing the Engine Air Filter (page 344).
E
Engine oil dipstick.
See Engine Oil Dipstick Overview (page 338).
F
Engine oil filler cap.
See Adding Engine Oil (page 338).
G
Windshield washer fluid reservoir.
See Adding Washer Fluid (page 118).
H
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ENGINE OIL
Engine Oil Dipstick Overview - 2.0L
Minimum.
A
Nominal.
B
Maximum.
C Engine Oil Dipstick Overview - 2.7L
Minimum.
A
Nominal.
B
Maximum.
C
Checking the Engine Oil Level
1. Make sure that your vehicle is on level ground.
2. Check the oil level before starting the engine, or switch the engine off after
warming up and wait 10 minutes for the
oil to drain into the oil pan. 3. Remove the dipstick and wipe it with a
clean, lint-free cloth.
4. Reinstall the dipstick and make sure it is
fully seated.
5. Remove the dipstick again to check the oil level.
Note: If the oil level is between the maximum
and minimum marks, the oil level is
acceptable. Do not add oil.
6. If the oil level is at the minimum mark, immediately add oil.
7. Reinstall the dipstick. Make sure it is fully
seated.
Note: The oil consumption of new engines
reaches its normal level after approximately
3,000 mi (5,000 km).
Adding Engine Oil WARNING:
Do not remove the filler
cap when the engine is running.
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CHECKING THE COOLANT
When the engine is cold, check the
concentration and level of the coolant at the
intervals listed in the scheduled maintenance
information. See Scheduled Maintenance
(page 459).
Note: Make sure that the coolant level is
between the minimum and maximum marks
on the coolant reservoir.
Note: Coolant expands when it is hot. The
level may extend beyond the
MAX mark.
If the coolant level is at or below the
minimum mark, add prediluted coolant
immediately.
Maintain coolant concentration within 48%
to 50%, which equates to a freeze point
between
-29°F (-34°C) and -35°F (-37°C).
Coolant concentration should be checked
using a refractometer. We do not recommend
the use of hydrometers or coolant test strips
for measuring coolant concentration. Adding Coolant WARNING:
Do not remove the
coolant reservoir cap when the engine is
on or the cooling system is hot. Wait 10
minutes for the cooling system to cool
down. Cover the coolant reservoir cap with
a thick cloth to prevent the possibility of
scalding and slowly remove the cap.
Failure to follow this instruction could result
in personal injury. WARNING:
Do not add engine
coolant when the engine is on or the
cooling system is hot. Failure to follow this
instruction could result in personal injury. WARNING:
Do not add coolant
further than the MAX mark. WARNING: Do not put coolant in the
windshield washer reservoir. If sprayed on
the windshield, coolant could make it
difficult to see through the windshield. Note:
Do not use stop leak pellets, cooling
system sealants, or non-specified additives
as they can cause damage to the engine
cooling or heating systems. Resulting
component damage may not be covered by
the vehicle Warranty.
Note: Automotive fluids are not
interchangeable.
It is very important to use prediluted coolant
approved to the correct specification in order
to avoid plugging the small passageways in
the engine cooling system.
See Capacities
and Specifications (page 407). Do not mix
different colors or types of coolant in your
vehicle. Mixing of engine coolants or using
an incorrect coolant may harm the engine or
cooling system components and could void
the vehicle Warranty.
Note: If prediluted coolant is not available,
use the approved concentrated coolant
diluting it to 50/50 with distilled water.
See
Capacities and Specifications (page 407).
Using water that has not been deionized
may contribute to deposit formation,
corrosion and plugging of the small cooling
system passageways.
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To top up the coolant level do the following:
1. Unscrew the cap slowly. Any pressure
escapes as you unscrew the cap.
2. Add enough prediluted coolant to reach
the correct level.
Note: We do not recommend the use of
recycled coolant.
3. Replace the coolant reservoir cap. Turn the cap clockwise until it contacts the
hard stop.
4. Check the coolant level in the coolant reservoir the next few times you drive
your vehicle. If necessary, repeat step 2.
If you have to add more than 1.1 qt (1 L) of
engine coolant per month, have your vehicle
checked as soon as possible. Operating an
engine with a low level of coolant can result
in engine overheating and possible engine
damage.
In case of emergency, you can add a large
amount of water without engine coolant in
order to reach a vehicle service location.
Service your vehicle as soon as possible. Water alone, without engine coolant, can
cause engine damage from corrosion,
overheating or freezing.
Do not use the following as a coolant
substitute, as they can cause engine damage
from overheating or freezing:
•
Alcohol.
• Methanol.
• Brine.
• Any coolant mixed with alcohol or
methanol antifreeze.
Do not add extra inhibitors or additives to
the coolant. These can be harmful and
compromise the corrosion protection of the
coolant.
Severe Climates
If you drive in extremely cold climates, you
may need to increase the coolant
concentration above 50%. Note:
A coolant concentration of 60%
provides improved freeze point protection.
Coolant concentrations above 60% decrease
the overheat protection characteristics of
the coolant and could cause engine
damage.
If you drive in extremely hot climates, you
may need to decrease the coolant
concentration to 40%.
Note: Coolant concentrations below 40%
decrease the freeze and corrosion protection
characteristics of the coolant and could
cause engine damage.
Coolant Change
Change the coolant at specific mileage
intervals. Refer to the scheduled
maintenance information.
See Normal
Scheduled Maintenance (page 463).
Note: Dispose of used coolant in the
appropriate manner.
Follow your community's regulations and
standards for recycling and disposing of
automotive fluids.
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Fail-Safe Cooling
Fail-safe cooling allows you to temporarily
drive your vehicle before any incremental
component damage occurs. The fail-safe
distance depends on ambient temperature,
vehicle load and terrain.
How Fail-Safe Cooling Works
If the engine begins to overheat,
the coolant temperature gauge
moves toward the red zone:
A warning lamp illuminates and a
message may appear in the
information display.
If the engine reaches a preset
over-temperature condition, the engine
automatically switches to alternating cylinder
operation. Each disabled cylinder acts as an
air pump and cools the engine.
When this occurs, your vehicle still operates,
however:
• Engine power is limited.
• The air conditioning system turns off. Continued operation increases the engine
temperature, causing the engine to
completely shut down. Your steering and
braking effort increases in this situation.
When the engine temperature cools, you can
re-start the engine. Have your vehicle
checked as soon as possible to minimize
engine damage.
When Fail-Safe Mode Is Activated
WARNING: Fail-safe mode is for use
during emergencies only. Operate your
vehicle in fail-safe mode only as long as
necessary to bring your vehicle to rest in
a safe location and seek immediate repairs.
When in fail-safe mode, your vehicle will
have limited power, will not be able to
maintain high-speed operation, and may
completely shut down without warning,
potentially losing engine power, power
steering assist, and power brake assist,
which may increase the possibility of a
crash resulting in serious injury. WARNING: Do not remove the
coolant reservoir cap when the engine is
on or the cooling system is hot. Wait 10
minutes for the cooling system to cool
down. Cover the coolant reservoir cap with
a thick cloth to prevent the possibility of
scalding and slowly remove the cap.
Failure to follow this instruction could result
in personal injury.
Your vehicle has limited engine power when
in the fail-safe mode, drive your vehicle with
caution. Your vehicle does not maintain
high-speed operation and the engine could
operate poorly.
Remember that the engine is capable of
automatically shutting down to prevent
engine damage. In this situation:
1. Pull off the road as soon as safely possible and switch the engine off.
2. If you are a member of a roadside assistance program, we recommend that
you contact your roadside assistance
service provider.
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3. If this is not possible, wait for a short
period of time for the engine to cool.
4. Check the coolant level. If the coolant level is at or below the minimum mark,
add prediluted coolant immediately.
5. When the engine temperature cools, you
can re-start the engine. Have your vehicle
checked as soon as possible to minimize
engine damage.
Note: Driving your vehicle without repair
increases the chance of engine damage.
Engine Coolant Temperature
Management (If Equipped) WARNING:
To reduce the risk of
crash and injury, be prepared that the
vehicle speed may reduce and the vehicle
may not be able to accelerate with full
power until the coolant temperature
reduces. If you tow a trailer with your vehicle, the
engine may temporarily reach a higher
temperature during severe operating
conditions, for example ascending a long or
steep grade in high ambient temperatures.
At this time, you may notice the coolant
temperature gauge moves toward the red
zone and a message may appear in the
information display.
You may notice a reduction in vehicle speed
caused by reduced engine power in order
to manage the engine coolant temperature.
Your vehicle may enter this mode if certain
high-temperature and high-load conditions
take place. The amount of speed reduction
depends on vehicle loading, grade and
ambient temperature. If this occurs, there is
no need to stop your vehicle. You can
continue to drive.
The air conditioning may automatically turn
on and off during severe operating
conditions to protect the engine from
overheating. When the coolant temperature
decreases to the normal operating
temperature, the air conditioning turns on. If the coolant temperature gauge moves fully
into the red zone, or if the coolant
temperature warning or service engine soon
messages appear in your information display,
do the following:
1.
Stop your vehicle as soon as it is safe to
do so. Fully apply the parking brake, shift
into park (P) or neutral (N).
2. Leave the engine running until the coolant temperature gauge needle
returns to the normal position. If the
temperature does not drop after several
minutes, follow the remaining steps.
3. Switch the engine off and wait for it to cool. Check the coolant level.
4. If the coolant level is at or below the minimum mark, add prediluted coolant
immediately.
5. If the coolant level is normal, restart the engine and continue.
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