No, you should never leave your car engine running while pumping gas. It is a significant safety hazard. The primary risk is the potential for a fire. A running engine produces heat, sparks from electrical components, and static electricity—all of which can ignite gasoline vapors that are always present during refueling. While modern vehicles and gas stations have safety features, the risk, however small, is not worth taking.
The practice can also cause issues with your car's onboard diagnostics. Many modern cars have sophisticated evaporative emission control (EVAP) systems designed to capture fuel vapors. Having the engine on can confuse the system's pressure tests, potentially triggering a check engine light.
Beyond the immediate danger, it's often against the law. Many states and local municipalities have explicit regulations prohibiting leaving a vehicle unattended with the engine running at a fueling station. Violating these rules can result in fines.
The safest procedure is simple: turn off the ignition, do not smoke, stay by your vehicle during the entire process, and touch a metal part of your car away from the filler neck to discharge static electricity before handling the nozzle. This minimizes all known risks.
| Supporting Data: Gas Station Fires & Regulations |
| :--- | :--- |
| The National Fire Protection Association (NFPA) cites hot engine parts, electrical arcs, and static discharge as ignition sources at fueling stations. | |
| A study by the Petroleum Equipment Institute found that static electricity is a leading cause of unexplained gas station fires. | |
| States like Massachusetts and New York have laws explicitly stating that a vehicle's engine must be off during refueling. | |
| Most major oil company safety protocols, like those from ExxonMobil and Shell, mandate that customers turn off engines. | |
| Modern EVAP systems perform a "leak test" only when the engine is off; refueling with it on can cause a faulty diagnostic code (e.g., P0455). | |
