How Does A Gas Pump Know When To Stop

Think about sucking air through a straw. When the end is open, it’s easy to suck in air. But if you put your finger over the end, you can’t suck in any more air. If you continue to suck, the pressure inside the straw decreases and it crumples in on itself. [2] X Research source

When this happens, slow the pump down. Either press lightly on the pump handle yourself, or move the pump handle clip to a lower position. [4] X Research source Flipping the pump nozzle upside down as you fuel up can also help the splash back issue.

If the pump continues to malfunction, tell your gas station attendant. There might be an issue inside the pump, which they can get fixed.

If you suspect the gas pump shuts off because your vent line is clogged or damaged, take your car to a mechanic. They can check if that’s the issue and fix or replace the line.

Overfilling your gas tank can also cause fuel to spill out of your car. This is dangerous to you, your car, and to the environment.