It’s a chilly day, and the thought of turning off your car while refueling in the freezing cold might cross your mind. You might even wonder, “Can I put gas in my car while it’s running?” After all, you’ve seen it done in racing events, and keeping the engine running seems like a way to maintain that precious cabin warmth. However, despite these fleeting thoughts, refueling your vehicle while the engine is running is generally discouraged and considered unsafe. Let’s delve into why it’s a bad idea to refuel with your engine running and what the best refueling practices are.
Why You Shouldn’t Refuel With the Engine Running
While the image of a car exploding into flames at a gas station might seem like something out of an action movie, the reality is that refueling while your engine is running does carry potential risks. Although fires directly caused by leaving engines running during refueling are not common, they are certainly not impossible. These incidents can occur due to a combination of factors, including stray sparks, electrical system malfunctions, or contact with extremely hot engine components.
According to the National Fire Protection Association (NFPA), gasoline’s autoignition temperature, the point at which it can spontaneously combust, is 536°F (280°C). This temperature threshold is surprisingly easy to reach in a running vehicle. Components in your exhaust system, such as catalytic converters, can reach temperatures between 800-1000°F during normal operation.
Alt text: Catalytic converter located underneath a vehicle, highlighting its position and potential proximity to gasoline vapors during refueling.
Considering that catalytic converters are positioned beneath vehicles, you might think the risk of gasoline vapors coming into contact with them is minimal. However, gasoline vapors are heavier than air, meaning they tend to sink and accumulate at the lowest point. In a gas station environment, this low point could very well be right under your car. While gas stations are open-air environments, promoting air circulation that usually disperses vapors, there’s still a chance for fumes to linger. So, while it’s unlikely your catalytic converter will ignite gasoline fumes immediately, the risk is still present. Why take that chance when simply turning off your engine eliminates it and allows the converter to cool down?
Furthermore, vehicles with faulty spark plugs can exacerbate the danger. When spark plugs misfire, unburnt fuel can enter the catalytic converter. This can lead to overheating of the catalyst, potentially damaging its internal structure over time. In severe cases, this can even result in red-hot particles being ejected from your exhaust pipe – a dangerous scenario when you are actively pumping flammable gasoline.
Beyond hot components, electrical faults within your car, such as shorts or worn wiring insulation, can also create ignition sources at the gas pump. A seemingly minor electrical issue can generate sparks. Turning off your vehicle significantly reduces the risk of these subtle electrical problems escalating into a fire hazard while refueling.
Even if your car is in excellent condition and the chances of a fire seem low, it’s always best to exercise caution. Moreover, most states adhere to the International Fire Code, which explicitly mandates that “the engines of vehicles being fueled shall be shut off during fueling.” Therefore, leaving your engine running while refueling isn’t just potentially risky; it’s also against regulations in many places.
Other Important Refueling Safety Tips
Beyond the critical step of turning off your engine, several other refueling practices contribute to your safety and the safety of others at the gas station.
Don’t Re-Enter the Vehicle During Refueling
Surprisingly, getting back into your car while refueling can be more dangerous than leaving the engine running. A study conducted by the Petroleum Equipment Institute (PEI) investigated 176 gas station fire incidents that weren’t attributed to open flames, running engines, or electrical issues. Remarkably, nearly 50% of these incidents—87 cases—occurred when individuals returned to their vehicle during refueling and then touched the fuel nozzle after exiting.
Alt text: A person holding a fuel nozzle while refueling a car at a gas station, illustrating the common activity that can pose static electricity risks.
The likely culprit in these fires is static electricity. Sliding across car seats, especially in dry conditions, can generate a static charge. When you then touch the metal fuel nozzle, this static electricity can discharge, potentially creating a spark strong enough to ignite gasoline vapors.
If you absolutely must re-enter your vehicle during refueling, ground yourself before touching the fuel nozzle again. The American Petroleum Institute (API) recommends doing this by touching a metal part of your car with your bare hand after getting out—your car door or any other metal surface away from the fuel filler area will work.
Unplug Any Charging Accessories
Minimizing electrical current flow in your car’s wiring harness is a key reason to turn off the engine before refueling. However, even with the car off, some circuits, like those powering cigarette lighters or USB ports, might still be active. For maximum safety, especially with older or modified vehicles, unplug any charging cords or electronic accessories before refueling, particularly if they show signs of wear or damage.
Don’t Smoke Near the Pump
The dangers of mixing gasoline and open flames are obvious. Like refueling with the engine running, smoking near a gas pump is almost certainly prohibited in your area, thanks to the International Fire Code. Refueling is a quick process, so it’s always safer to wait until you are well away from the gas station to light up.
Don’t “Top Off” Your Tank
“Topping off” refers to the practice of adding more fuel to your tank after the pump has automatically stopped, indicating a full tank. While some believe this squeezes in a bit more mileage, it can harm your car and create a fire hazard if the tank overflows.
The Environmental Protection Agency (EPA) explains that most cars manufactured since the early 2000s are equipped with onboard refueling vapor recovery (ORVR) systems. These systems are designed to capture fuel vapors during refueling, preventing them from escaping into the atmosphere, thus reducing pollution and fire risks at gas stations. ORVR systems use carbon canisters to store these vapors, which are then drawn into the engine and burned as fuel when the car is running. Topping off your tank can flood the ORVR system, potentially shortening its lifespan and even causing engine performance issues.
Refrain from Using Your Cell Phone
Gas stations often display warnings against cell phone use near the pumps. In the past, there were concerns that cell phones could emit sparks and ignite fuel vapors. However, extensive testing by the NFPA and the Federal Communications Commission (FCC) has concluded that cell phones do not pose a fire hazard at gas pumps. The signs are mainly in place to minimize liability for gas station owners and to reduce distractions.
So, while using your phone while pumping gas isn’t a fire risk, it can be a distraction. Refueling requires your attention, and it’s always best to be fully present and aware in case any unexpected situation arises.
Bonus Tip: Protect Your Vehicle with Fuel System Maintenance
Adhering to safe refueling practices is essential for preventing fire hazards, but maintaining your vehicle’s fuel system is also crucial for overall safety and performance. Regular fuel system cleanings and fuel filter replacements (if your vehicle is equipped with one) are vital preventative measures. A neglected fuel system can lead to problems like rough idling, decreased engine performance, increased emissions, and reduced fuel efficiency. Consult your local automotive service professionals, such as the technicians at Firestone Complete Auto Care, to schedule your fuel system maintenance and ensure your vehicle remains in top condition. Book your fuel system maintenance appointment today!
