No, you should never leave your car engine running while pumping gas. It is a significant safety hazard. The primary risk is that a stray spark, which can come from the engine bay or even static electricity from your body, could ignite gasoline vapors, leading to a fire or explosion. While modern vehicles and gas pumps have safety features, the potential consequences are too severe to ignore. Turning off the engine is a simple, non-negotiable step for everyone's safety.
The core danger lies in the properties of gasoline. It's the flammable vapor, not the liquid itself, that is most dangerous. These vapors are heavier than air and can travel along the ground. A running engine contains multiple ignition sources: the electrical system, hot exhaust components, and the engine's operation itself (like sparks from the alternator). Although the probability might seem low, the National Fire Protection Association (NFPA) codes explicitly state that engines should be switched off during refueling.
Beyond the extreme fire risk, there are other good reasons to turn your car off. A running engine consumes fuel unnecessarily, counteracting the gas you're putting in. It also increases emissions at the pump, contributing to local air pollution. Some states even have laws making it illegal to leave your vehicle unattended with the engine running, which includes stepping away to use the payment kiosk while the pump is active.
The safe procedure is straightforward: turn off the ignition, remove the keys, and if you need to get back in the car during fueling (for example, to get your wallet), be sure to touch a metal part of the car's body away from the filler neck to discharge any static electricity before touching the gas nozzle again. This simple habit effectively eliminates the risk.
