Why does the fuel nozzle keep shutting off when refueling a new car?

[LaOscar]

The fuel nozzle is the terminal output of the fuel dispenser at gas stations, which is the part that comes into contact with the vehicle's fuel tank. The commonly used types are self-sealing fuel nozzles and composite fuel nozzles. The following are the reasons why the fuel nozzle shuts off ("jumps") when refueling a new car: 1. Fuel nozzle issue: The nozzle tip is equipped with a self-sealing (shutoff) device that is highly sensitive, designed to prevent fuel from spilling out during refueling. When the tank is nearly full, fuel rises and touches this device, causing the nozzle to automatically close and stop fueling, resulting in a "nozzle jump." There's also a "pre-full jump" scenario. The fuel dispenser operates as a closed system, relying on internal oil pressure. If the nozzle has high pressure, fuel may splash back to the nozzle tip, triggering a "jump." 2. Other factors: "Nozzle jumps" can also be related to ambient temperature and refueling speed. High temperatures increase pressure inside the fuel tank, and rapid refueling further elevates this pressure, making fuel more likely to splash and causing frequent "nozzle jumps." Therefore, "nozzle jumping" during refueling is a normal phenomenon.

[VanMakayla]

When I first got my new car, the fuel pump nozzle kept clicking off, which was really frustrating. This happens because new car fuel tanks have excellent sealing, and during refueling, the air can't escape properly, causing pressure to build up and splash fuel back into the nozzle, triggering the automatic shut-off. Common causes include a clogged fuel tank ventilation system (charcoal canister), fuel pipe design issues, or the car not being fully broken in. Ignoring this issue can lead to slower refueling at best, or affect emissions and even cause smoke at worst. If you encounter this problem, don't panic. Try slowing down the refueling speed and not inserting the nozzle too deep to allow for stable airflow. If that doesn't help, check if the charcoal canister is dirty or has oil buildup. You can remove and clean it yourself or use high-pressure air to blow it clear, but it's best to have it handled by a professional shop. New cars often have this issue, and it usually improves after some driving. Remember to wait a few seconds after refueling before removing the nozzle to prevent residual pressure.

[Ricardo]

I've been studying cars for several years, and the fuel pump nozzle shut-off issue is quite interesting. It's mainly caused by the air pressure imbalance in the fuel tank of new cars, which pushes the fuel back and triggers the safety mechanism. Possible reasons include a clogged charcoal canister system, the new fuel tank not being fully adapted, or the fuel flow being too fast during refueling. I once encountered less frequent shut-offs in cold weather but more frequent ones in hot weather due to thermal expansion affecting pressure. It's recommended that owners refuel at a moderate speed and avoid inserting the nozzle too deep. Additionally, regularly check if the charcoal canister filter is clogged with dust—it can be gently cleaned with a soft brush, but safety precautions should be taken. Before resolving the issue, avoid forcing fuel in to prevent gasoline leaks and potential hazards. In the long run, maintaining vehicle cleanliness and proper refueling habits can reduce the problem. Beginners will get the hang of it after observing a few times.

[AustinAnn]

I just bought a new car, and the fuel pump keeps clicking off when refueling. My friend said not to worry too much; it's mostly caused by trapped air in the fuel tank creating pressure. New cars with tight sealing designs often have this issue. The solution is simple: push the handle slowly when refueling, don’t pump too aggressively. If it still clicks off, check if the fuel cap is tightly screwed on or has cracks, and ensure the charcoal canister ventilation system is clear—you can visually inspect these yourself. If the problem persists, take it to the dealership for a free repair since the car is still under warranty. When refueling, choose a level spot and avoid slopes—after a few tries, the issue usually lessens. For safety, pause for a few minutes if the pump clicks off before continuing to refuel.