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General Interest

Do You Wait Until the Fuel Light Comes on to Fill Your Gas Tank?

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Are you one of those people who doesn't put gas into your tank until it beeps a warning? I’ve known a few people who do this on a regular basis and I’ve seen the damage first hand.

Most vehicles have an electric fuel pump. This sits inside the tank and is submerged in fuel, which keeps the pump cool and lubricated. Without this submergence in fuel, the pump can self destruct from overheating. The reserve fuel inside your tank prevents this from happening.

Some vehicles have a well that the pump sits inside and if this well runs dry, the pump also gets damaged. If your vehicle is fueled by diesel and this occurs, it also becomes necessary to “prime it” to get fuel to the pump.

Heat also plays a factor. When you have 90 degree days coupled with the heat from the pavement on the bottom side of the car where the fuel tank sits, it does not take much for the pumps to go bad.

If you regularly put in just enough gas to get by, your fuel pump can fail earlier than normal. Your pump will also be taking in the “bottom of the barrel” fuel, which is full of debris. This sediment in the bottom of the fuel tank can also clog the fuel filter, fuel injectors, and the pump pickup. I generally don’t let my tank get below 1/4 tank for this reason.

The best thing you can do for your vehicle is fill it up when it gets to a quarter tank. It will save you money in the long run and keep your car running well. Sure, it doesn’t have the same challenge as driving on fumes, but when it comes to your vehicle, it's always wise to consider damage control … both to your car and your wallet!

Happy Motoring!

Add a Comment (1) Comments
  • Visitor, February 07, 2014, 15:46

    So far I've only heard the second reason -- running it too low has the pump sucking up the debris at the bottom -- but how low can you go before that's really a problem? Most Japanese cars, at least, set off the warning light when there are still 3-4 gallons left, meaning you're good for another ~100 miles. With such a comfortable margin, filling up before that seems wasteful. As for the first reason, are fuel pumps really flimsy enough to fail without being totally submerged in fuel?

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