Chevrolet GMC Duramax 2023 Manual page 27

26 Driving and Operating
Recommended
Problem
Immediately after A large amount of
refueling, message water is in the fuel
displays and tank. Drain the fuel
stays on. filter immediately.
If the message stays
on or comes back
on without
refueling, then fuel
tank purging is
required. See your
dealer. If the
message displays
and the engine
stalls or runs rough,
do not drive until
the water
contaminated fuel is
drained.
Caution
Driving with this message on can damage
the fuel injection system and the engine.
If the message comes on right after a
Action
refuel, water was pumped into the fuel
tank. Turn off the engine and drain the
water immediately.
Removing Water from the Fuel Filter
To drain water:
1. Turn the engine off and apply the
parking brake.
2. Place a container under the filter drain
valve. The filter drain valve is on the
bottom of the fuel filter. The filter drain
valve is under the vehicle on the driver
(Continued)
side, inside the frame rail.
Caution (Continued)
3. Open the drain valve by turning it
counterclockwise. Allow the filter to
drain until all of the water has been
removed. Close the valve.
4. Properly dispose of the water
contaminated fuel.
5. Start the engine and let it run for a few
minutes. During the draining process, air
may have entered the fuel system. If the
engine stalls, the fuel system may need
to be primed. See Fuel Priming
following.
Fuel Priming
For the fuel system to work properly, the
fuel lines must be full of fuel. If air gets in,
the fuel lines need to be primed before
operating the vehicle.
If air is present, the following may have
happened:
The vehicle ran out of fuel.
The fuel filter was removed.
The fuel lines were removed or
disconnected.
The fuel filter water drain valve was
opened while the engine was running.