GMC 1993 Safari Owner's Manual page 121

Fuel Gage
Standard Chster
0
FUEL
PO651
The fuel gage tells you how much fuel you have remaining, when the ignition
is on. When the gage first indicates empty you still have a little fuel left, but
you should get more fuel as soon as possible.
A box around the fuel gage symbol on the digital cluster will begin to flash
when your tank is 1/8 full or less.
Here are four things some owners ask about. None of these indicate a
problem with your fuel gage:
At the gas station, the gas pump shuts off before the gage reads full.
The fuel tank will take either a little more or a little less fuel to fill up
The gage moves a little when you turn a corner or speed up.
The gage doesn't go back to empty when you
turn off the ignition.
than the gage shows.
For your fuel tank capacity, see the Index under "Fluid Capacities."
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