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Chevrolet/GMC 2.8L Duramax Diesel Engine Supplement (GMNA-Localizing-
U.S./Canada-13336155) - 2020 - CRC - 5/6/19
Driving and Operating
35
Caution
Water in the diesel fuel can
corrode internal components of
the fuel system and lead to
severe damage. It can also
support fungus or bacteria
growth, which can damage the
fuel system and Fuel Operated
Heater (FOH) (if equipped). Even
with a diesel fuel biocide, the fuel
system may still need to be
cleaned. Your dealer can advise
of the appropriate solution.
If the fuel tank needs to be
purged to remove water, see your
dealer or a qualified technician.
Improper purging can damage the
fuel system and block the FOH.
Water in Fuel Troubleshooting
If the WATER IN FUEL SERVICE
REQUIRED message comes on:
Problem
Recommended
Action
Message
displays but
goes off during
the ignition
cycle.
The fuel filter is
partially filled
with water. Drain
the water as
soon as
possible. See
"Removing
Water from the
Fuel Filter"
following.
Problem
Recommended
Action
Message
displays and
stays on.
Drain the fuel
filter
immediately.
If no water can
be drained, and
the temperature
is below
freezing, then
water may be
frozen in the
filter. Move the
vehicle to a
warm location to
thaw the water,
then drain the
fuel. If water still
does not drain,
see your dealer.