GMC 2011 Sierra Owner's Manual page 383

Fuel can spray out on you if you
open the fuel cap too quickly.
If you spill fuel and then
something ignites it, you could be
badly burned. This spray can
happen if the tank is nearly full,
and is more likely in hot weather.
Open the fuel cap slowly and wait
for any hiss noise to stop. Then
unscrew the cap all the way.
If the vehicle is a dual fuel tank
chassis cab model, and it runs out
of fuel, refuel the front fuel tank first
to ensure a quick restart.
Be careful not to spill fuel. Do not
top off or overfill the tank and wait a
few seconds after you have finished
pumping before removing the
nozzle. Clean fuel from painted
surfaces as soon as possible.
See
When replacing the fuel cap, turn it
clockwise until it clicks. It will require
more effort to turn the fuel cap on
the last turn as you tighten it. Make
sure the cap is fully installed. The
diagnostic system can determine if
the fuel cap has been left off or
improperly installed. This would
allow fuel to evaporate into the
atmosphere. See
The TIGHTEN GAS CAP message
displays on the Driver Information
Center (DIC) if the fuel cap is not
properly installed. See
information.
If a fire starts while you are
.
refueling, do not remove the
nozzle. Shut off the flow of fuel
by shutting off the pump or by
notifying the station attendant.
Leave the area immediately.
.
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