Should You Turn Off the Engine Before Opening the Fuel Tank When Refueling a Car?
3 Answers
When refueling a car, you should turn off the engine before opening the fuel tank. Here are some refueling precautions: 1. Use automotive gasoline only, as inappropriate fuel entering the fuel system may damage both the fuel system and the engine; 2. Do not use gasoline containing methanol or alcohol; 3. Avoid spilling fuel on painted surfaces to prevent paint damage; 4. If the fuel tank door is frozen and cannot be opened, gently push or tap the door to remove ice and open it; 5. Prevent excessive fuel pressure that could cause spraying; 6. Insert the fuel nozzle deep into the tank to avoid overflow or spillage, which could lead to fire or explosion; 7. Before opening the fuel filler cap or touching the fuel nozzle, touch the car body to discharge static electricity, and avoid re-entering the vehicle during refueling to prevent static buildup.
I remember when I first bought my car, I also struggled with the refueling sequence. Once, I saw a friend refueling without turning off the engine, and the staff member shouted through the window, 'Turn off the engine!' It scared me so much that I made sure to remember this rule. When the engine is running, not to mention the risk of static electricity on the car body, the exhaust pipe temperature is close to 1000°C, and the volatile oil vapor near the fuel tank may ignite when exposed to heat. For us ordinary car owners, just remember three steps: first, turn off the engine when entering the gas station, then open the car door to unscrew the fuel tank cap, and after refueling, reverse the operation for safety. I once witnessed a car bursting into flames with a 'bang' next to the fuel dispenser because the engine wasn't turned off, and it still gives me chills thinking about it now.
Having worked in car repair for twenty years, I've encountered the strange phenomenon of a fuel tank cap being sucked in by the gas pump nozzle seven or eight times. When the engine is running, the gasoline vapor pressure inside the tank is higher than usual, and suddenly opening the cap may cause oil mist to spray out. Last week, a regular customer brought in their Wrangler to replace the fuel tank cap seal ring—the latch broke because they forced the cap open without turning off the engine. According to the automaker's repair manual, it's ideal to wait thirty seconds after turning off the engine before opening the cap, as this allows the fuel system to complete its pressure release. On scorching summer days, it's even safer to touch the door handle a couple of times to discharge static electricity before handling the cap.
