No, you should not fill your gas tank with the car's engine running. It is a significant safety hazard. While the odds of an incident are low, the potential consequences are severe, including fire or explosion. The primary risk stems from static electricity or a stray spark igniting gasoline vapors, which are always present during refueling. A running engine provides multiple potential ignition sources, such as electrical components, hot exhaust parts, and the alternator.
The National Fire Protection Association (NFPA) codes explicitly recommend turning off your vehicle during refueling. This simple action is the most effective way to minimize risk. Beyond the engine, you should also avoid activities that could generate sparks, like re-entering your vehicle (which can build static electricity) or using cell phones.
Most modern vehicles have sophisticated evaporative emissions systems designed to capture fuel vapors. Refueling with the engine on can potentially confuse these systems and trigger a check engine light. While not dangerous, it's an unnecessary hassle.
The safest and most correct procedure is straightforward: turn off the engine, refrain from smoking or using electronic devices, and stay near the fuel nozzle until the process is complete.
| Supporting Data: Gas Station Fires & Ignition Sources (Representative Data) |
| :--- | :--- |
| An estimated 5,020 structure fires at service stations occurred annually in the US (2004-2008 data). | |
| Heating (19%) was the leading cause of fires at stations, followed by incendiary/suspicious causes (16%). | |
| Vehicle-related incidents accounted for 4% of these fires but had a high potential for severity. | |
| The majority of refueling-related fires are initiated by static electricity discharge, not the vehicle's engine. | |
| A running engine's under-hood temperature can exceed 200°F (93°C), well above gasoline's flash point of -45°F (-43°C). | |
| Modern gasoline formulations have a high vapor pressure, meaning vapors are readily released during fueling. | |
| NFPA 30A, the code for motor fuel dispensing facilities, advises shutting off engines during refueling. | |
