When filling up gas in a car why does the first notch at full take the longest to go down, then all subsequent notches go faster?

Question

When filling up gas in a car why does the first notch at full take the longest to go down, then all subsequent notches go faster?

In: 0

Answer 1

The fuel gauge is connected to a float in the gas tank. As the level of gas goes down, the height of the float changes, which causes the gauge to change.

But they’re not always calibrated perfectly, so the top gallon or so of the gas tank may be above the gauge’s range, so to speak.