Chevrolet 1999 Express Van Owner's Manual page 131

Listed are four situations you may experience with your
fuel gage:
D
At the gas station, the fuel pump shuts off before the
gage reads F (Full).
D
It takes a little more or less fuel to fill up than the
fuel gage indicated. For example, the gage may have
indicated the tank was half full, but it actually took a
little more or less than half the tank's capacity to fill
the tank.
D
The gage moves a little when you turn a corner or
speed up.
D
The gage doesn't go back to E (Empty) when you
turn off the ignition.
None of these indicate a problem with the fuel gage.
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