engine overheat FORD FLEX 2011 1.G User Guide

Severe climates
If you drive in extremely cold climates (less than –34°F [–36°C]):
•It may be necessary to increase the coolant concentration
above 50%.
•NEVER increase the coolant concentration above 60%.
•A coolant concentration of 60% will provide freeze point
protection down to -62°F [-52°C]. Increased engine coolant
concentrations above 60% will decrease the overheat
protection characteristics of the engine coolant and may cause
engine damage.
•If available, refer to the chart on the coolant container to
ensure the coolant concentration in your vehicle will provide
adequate freeze protection at the temperatures in which you
drive in the winter months.
If you drive in extremely hot climates:
•It is still necessary to maintain the coolant concentration
above 40%.
•NEVER decrease the coolant concentration below 40%.
•A coolant concentration of 40% will provide freeze point
protection down to -12°F [-24°C]. Decreased engine coolant
concentrations below 40% will decrease the corrosion/freeze
protection characteristics of the engine coolant and may cause
engine damage.
•If available, refer to the chart on the coolant container to
ensure the coolant concentration in your vehicle will provide
adequate protection at the temperatures in which you drive.
Vehicles driven year-round in non-extreme climates should use a 50/50
mixture of engine coolant and distilled water for optimum cooling system
and engine protection.
Engine fluid temperature management (EcoBoost™ engine only)
Your vehicle has been designed to pull a trailer, but because of the added
load, the vehicle’s engine may temporarily reach higher temperatures
during severe operating conditions such as ascending a long or steep
grade while pulling a trailer in hot ambient temperatures.
At this time, you may notice your engine coolant temperature gauge
needle move toward the H and the POWER REDUCED TO LOWER
TEMP message may appear on the message center.
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You may notice a reduction in the vehicle’s speed caused by reduced
engine power. Your vehicle has been designed to enter this mode if
certain high temperature/high load conditions take place in order to
manage the engine’s fluid temperatures. The amount of speed reduction
will depend on the vehicle loading, towing, grade, ambient temperature,
and other factors. If this occurs, there is no need to pull off the road.
The vehicle can continue to be driven while this message is active.
WARNING:To reduce the risk of collision and injury, be
prepared that the vehicle speed may reduce and the vehicle may
not be able to accelerate with full power until the fluid temperatures
reduce.
The air conditioning may also cycle on and off during severe operating
conditions to protect overheating of the engine. When the engine coolant
temperature decreases to a more normal operating temperature, the air
conditioning will turn on once again.
If you notice any of the following:
•the engine coolant temperature gauge moves fully into the red (hot)
area
•the coolant temperature warning light illuminates
•the service engine soon indicator illuminates
1. Pull off the road as soon as safely possible and place the vehicle in P
(Park).
2. Leave the engine running until the coolant temperature gauge needle
moves away from the H range. After several minutes, if this does not
happen, follow the remaining steps.
3. Turn the engine off and wait for it to cool before checking the coolant
level.
WARNING:Never remove the coolant reservoir cap while the
engine is running or hot.
4. If the coolant level is normal, you may restart your engine and
continue on.
5. If the coolant is low, add coolant, restart the engine and take your
vehicle to an authorized dealer. SeeAdding engine coolantin this
chapter for more information.
Refer to fail-safe cooling for additional information.
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What you should know about fail-safe cooling
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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Your vehicle is very sophisticated and built with multiple complex
performance systems. Every manufacturer develops these systems using
different specifications and performance features. That’s why it’s
important to rely upon your Ford or Lincoln Mercury dealership to
properly diagnose and repair your vehicle.
Ford Motor Company has recommended maintenance intervals for
various parts and component systems based upon engineering testing.
Ford Motor Company relies upon this testing to determine the most
appropriate mileage for replacement of oils and fluids to protect your
vehicle at the lowest overall cost to you and recommends against
maintenance schedules that deviate from the scheduled maintenance
information.
Ford strongly recommends the use of genuine Ford replacement parts.
Parts other than Ford, Motorcraftor Ford-authorized remanufactured
parts that are used for maintenance replacement or for the service of
components affecting emission control must be equivalent to genuine
Ford Motor Company parts in performance and durability. It is the
owner’s responsibility to determine the equivalency of such parts. Please
consult yourWarranty Guidefor complete warranty information.
Non-Ford approved chemicals or additives are not required for factory
recommended maintenance. In fact, Ford Motor Company recommends
against the use of such additive products unless specifically
recommended by Ford for a particular application.
Oil, fluids and flushing
In many cases, fluid discoloration is a normal operating characteristic
and, by itself, does not necessarily indicate a concern or that the fluid
needs to be changed. However, discolored fluids that also show signs of
overheating and/or foreign material contamination should be inspected
immediately by a qualified expert such as the factory-trained technicians
at your Ford or Lincoln Mercury dealership. Your vehicle’s oils and fluids
should be changed at the specified intervals or in conjunction with a
repair. Flushing is a viable way to change fluid for many vehicle
sub-systems during scheduled maintenance. It is critical that systems are
flushed only with new fluid that is the same as that required to fill and
operate the system, or using a Ford-approved flushing chemical.
Genuine Ford parts and service
When planning your maintenance services, consider your Ford and
Lincoln Mercury dealership for all your vehicle’s needs.
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