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Battery relearn
Because your vehicle’s engine is electronically controlled by a computer,
some control conditions are maintained by power from the battery. When
the battery is disconnected or a new battery is installed, the engine must
relearn its idle and fuel trim strategy for optimum driveability and
performance. Flexible fuel vehicles (FFV) must also relearn the ethanol
content of the fuel for optimum driveability and performance. To begin
this process:
1. With the vehicle at a complete stop, set the parking brake.
2. Put the gearshift in P (Park), turn off all accessories and start the
engine.
3. Run the engine until it reaches normal operating temperature.
4. Allow the engine to idle for at least one minute.
5. Turn the A/C on and allow the engine to idle for at least one minute.
6. Release the parking brake. With your foot on the brake pedal and with
the A/C on, put the vehicle in D (Drive) and allow the engine to idle for
at least one minute.
7. Drive the vehicle to complete the relearning process.
•The vehicle may need to be driven 10 miles (16 km) or more to
relearn the idle and fuel trim strategy along with the ethanol content
for flexible fuel vehicles.
•If you do not allow the engine to relearn its idle trim, the idle quality
of your vehicle may be adversely affected until the idle trim is
eventually relearned.
•For flexible fuel vehicles, if you are operating on E85, you may
experience poor starts or an inability to start the engine and
driveability problems until the fuel trim and ethanol content have been
relearned.
If the battery has been disconnected or a new battery has been installed,
the clock and radio settings must be reset once the battery is
reconnected.
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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.
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
indicator light will
illuminate.
•The
indicator light will flash when fail-safe cooling mode has
been activated.
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 an authorized dealer 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.
2008 Econoline(eco)
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At the next opportunity, safely pull off of the road, remove the fuel filler
cap, align the cap properly and reinstall it. The check fuel cap
light
or “check fuel cap” message may not reset immediately; it may
take several driving cycles for the check fuel cap light
or “check fuel
cap” 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 and
highway driving.
Continuing to drive with the check fuel cap light
or “check fuel cap”
message on may cause the
light to turn on as well.
If you must replace the fuel filler cap, replace it with a fuel filler
cap that is designed for your vehicle. The customer warranty may
be void for any damage to the fuel tank or fuel system if the
correct genuine Ford, Motorcraft or other certified fuel filler cap
is not used.
WARNING:The fuel system may be under pressure. If the fuel
filler cap is venting vapor or if you hear a hissing sound, wait
until it stops before completely removing the fuel filler cap. Otherwise,
fuel may spray out and injure you or others.
WARNING:If you do not use the proper fuel filler cap,
excessive vacuum in the fuel tank may damage the fuel system
or cause the fuel cap to disengage in a collision, which may result in
personal injury.
FFV (Flex Fuel Vehicle) fuel cap
If your vehicle is FFV capable, it will have a yellow colored fuel cap.
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