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4. Turn the ignition key to START for 10 to 15 seconds
at a time until your engine starts. If the engine tries
to run, but does not run smoothly, increase the rpm
a little using the accelerator pedal. This will help
force air through the system.
Your service engine soon light may come on if the
vehicle has run out of fuel. This light may stay on for a
few drive cycles after the condition is corrected, but
will eventually clear itself.
Fuel Filter Replacement
If you want to change the diesel engine fuel filter
yourself, here is how to do it:
{CAUTION:
Diesel fuel is ammable. It could start a re if
something ignites it, and you could be burned.
Do not let it get on hot engine parts, and keep
matches or other ignition sources away.
First, drain any water from the filter by following the
water draining procedure earlier in this section.
Your vehicle’s engine should be off until the end of this
procedure.If your vehicle has the 6.6L engine, the fuel filter is
located in the engine compartment on the driver’s side
of the vehicle. If your vehicle has either the 7.2L or
7.8L engine, the fuel filters are located in the engine
compartment on the driver’s side of the vehicle, and on
the driver’s side frame rail in front of the fuel tank.
1. Apply the parking brake.
2. Unplug the water
sensor wire connected
to the fuel filter and
unscrew the filter
element.
3. Remove the filter element. If there is any dirt on the
filter sealing surface, clean it off. Remove and reuse
the water sensor float switch located on the bottom of
the fuel filter.
4. Install the new filter element.
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5. Reinstall and tighten the filter container and
reconnect the water sensor wire to the filter.
6. Use the fuel filter priming procedure earlier in this
section to prime the fuel filter.
7. Tighten the air bleed valve by turning it clockwise
until hand-tight.
8. Start your engine and let it idle for five minutes.
Check your fuel filter and air bleed valve for
leaks.
How to Reset Fuel Filter Change
Light - DURAMAX®6.6L (LMM) Engine
The engine controller calculates when to change
the fuel filter based on vehicle and fuel use. Anytime
your fuel filter is changed, reset the fuel filter light so the
engine controller can calculate when the next fuel filter
change is required. If a situation occurs where you
change your fuel filter prior to a change fuel filter light
being turned on, reset the fuel filter change light.To reset the Fuel Filter Change light:
1. Turn the ignition key to RUN with the engine off
2. Fully press the accelerator and brake pedals at the
same time for 10 seconds. If the Fuel Filter Change
light flashes for 5 seconds, the system is resetting.
3. Turn the key to OFF
If the Fuel Filter Change light comes back on when you
start your vehicle, the light has not been reset. Repeat
the procedure. SeeChange Fuel Filter Warning Light on
page 3-44for more information.Fuels in Foreign Countries
If you plan on driving in another country outside the
United States or Canada, the proper fuel might be hard
to find. Never use leaded gasoline or any other fuel
not recommended in the previous text on fuel. Costly
repairs caused by use of improper fuel would not be
covered by your warranty.
To check the fuel availability, ask an auto club, or
contact a major oil company that does business in the
country where you will be driving.
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If you have dual tanks, fill the driver’s side tank, or
forward tank, first. The fuel gage will give better readings
this way. Your gage will show the total fuel left in both
tanks.
If your vehicle is a C4/C5 model and you have dual
tanks, the engine must be off when refueling or the fuel
transfer system may become inoperable.
If you have a single tank with dual fillers, where there is
a filler on each side of the vehicle, do not attempt to
fill the tank through both fillers at the same time. Also,
do not fill the tank with both caps removed, as this
may result in over-filling the tank and fuel spillage.Filling a Portable Fuel Container
{CAUTION:
Never ll a portable fuel container while it is in
your vehicle. Static electricity discharge from
the container can ignite the fuel vapor. You
can be badly burned and your vehicle
damaged if this occurs. To help avoid injury to
you and others:
Dispense fuel only into approved
containers.
Do not ll a container while it is inside a
vehicle, in a vehicle’s trunk, pickup bed, or
on any surface other than the ground.
Bring the ll nozzle in contact with the
inside of the ll opening before operating
the nozzle. Contact should be maintained
until the lling is complete.
Do not smoke while pumping fuel.
Do not use a cellular phone while
pumping fuel.
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