Why Turn the Car off When Pumping Gas?

A common dilemma most drivers face during their drives is whether to turn off their car when pumping gas or not. Generally, we don’t attach much stigma to either choice. However, this decision has much more than simply complying with the gas station rules. Here, we will consider some of the main reasons why your engine must be turned off when pumping fuel into the car.

The Mechanics of the Engine

Don’t worry! We won’t go into deep details here about the engine functionality. Instead, consider that air and gasoline form a mixture inside the engine, then ignite through the spark plugs to generate energy. Although the process is safe when the car is in drive mode, the explosive nature of the process becomes unsafe when the gas is being filled. The static electricity from the engine can light the gasoline through a single spark. If the spark reaches out while filling the gas, it can light up your entire car, if not the entire refilling station.

Static Electricity Generation

Gas vapors that leave the tank during the gas filling process are a serious concern. These gas vapors can ignite if they contact static electricity like the one inside your engine. If you wonder where the spark would come from when filling the gap, it would be your fingertips! Every time you enter or exit your car, a small electric charge is built upon you, especially during winter. In winters, the clothing fabric can rub against the seat and increase the charge. If you touch the metallic part of the gas pump, it will ignite a spark, which may cause a fire.

Other Precautions

Apart from turning off your engine, you must also consider other precautions.

  • Touch any metal surface for a few seconds before starting to refill your car. This way, the charge on your body is removed, nullifying the chances of a spark.
  • Don’t carry any electronic device in your hand or clothes when refilling the gas tank. Instead, keep them away to avoid a spark generation.
  • Wear anti-charge gloves when filling in the gas to avoid chances of fire.

Is It Impossible To Fill Gas In the Car When The Engine is On?

Technically speaking, no. You can fill in the gas tank while the engine is on. However, the best is to avoid leaving your engine on when refilling for all practical safety purposes. 

More importantly, it is preferable if car companies provide sensors or other functions to ensure that the cars are turned off at the time of refill. Furthermore, avoid breaking the gas station rules as well. Most gas stations have clear signs requiring your vehicle to be turned off when refilling.


It is preferable to turn off your car’s engine when filling gas in the car to ensure safety. Let us know in the comments section if the article was helpful.