Help: My gas tank was gushing like Ol' Faithful at the pump!

Dear Car Talk

Dear Car Talk | Jul 01, 2005

Dear Tom and Ray:

I was pumping gas today, and it generally costs around $35 to fill my tank. Today, the meter went up to $40, and I thought it was because the price of gas went up again. But since I only had $40, I had to stop pumping. When I pulled the hose out of the gas-tank opening, gasoline started shooting out of the gas-tank opening! It was not just dribbling down the side of my car -- it looked like a fountain! There was gas all over me, the concrete, the gas pumps, etc. When it finally subsided, I realized that my entire lap area felt like it was on fire from the gasoline that soaked through my jeans! All I could think about was getting home and getting those clothes off, so I jumped into the car, drove home, pulled everything off, jumped into a tub of water and waited for the burning to stop. After drying off and applying two tubes of Neosporin, I finally felt better. But what happened?! -- Donna

RAY: Well, the good news is, you'll save money this summer because you've already got your Brazilian wax!

TOM: This is why there's no smoking allowed at gas stations, Donna. Stuff can happen.

RAY: In your case, it was most likely a faulty gas-pump nozzle. There's an automatic shut-off device in the nozzle that senses the back pressure coming out of the tank. That's how the nozzle knows when your tank is full and it's time to cut off the fuel flow. My guess is that the shut-off device on the pump you used was broken.

TOM: While you were pumping the gas, the nozzle itself and the positive pressure of the incoming gasoline were preventing the gas from shooting back out. Meanwhile, the plastic gas tank in your car was bulging and expanding to accommodate the extra fuel. Then as soon as you stopped pumping and removed the nozzle, the tank returned to its normal shape, and bada-bing! There's Old Faithful!

RAY: As you discovered, Donna, gasoline is a skin irritant. The more sensitive the skin, the more it irritates. But I bet it still beats a Brazilian wax!

TOM: The other possibility is that something's wrong with the evaporative emissions system in your car. But since this has never happened to you at any other gas station, I'd be more inclined to blame the automatic shut-off device on that particular pump.

RAY: So, I'd do a couple of things, Donna. (Aside from switching to rubber underwear.) First, I'd report the problem to the gas-station manager. Second, I'd stand to the side when removing the nozzle -- at least for a while, until you're sure that it was the pump and not your car. And if you DO experience this again at a different pump, definitely ask your mechanic to look at your evaporative emissions system.

TOM: And finally, make sure you grind out those fat stogies before you pump gas from now on. Good luck, Donna.

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