MINNEAPOLIS - Via Twitter, our viewer Malorie asks, "Is it true that you need to keep a 1/4 tank of gas in your car when it's this cold? If so, why? Or is that a myth?"
For the answer, we turned to Dunwoody College of Technology's Stephan Reinarts. He says, "The answer to that is true. What the fuel pump does is supply fuel from the tank to the engine. Inside this cavity is the fuel pump itself...surrounded by fuel. By letting it drop below a quarter of a tank, that level drops below the fuel pump module and that will cause it to overheat. The fuel actually cools the fuel pump."
So the quarter tank rule should remain in effect, no matter what the outside temperature, if you want a functioning fuel pump. Replacing one could cost hundreds of dollars.
Another concern for drivers: under-inflated tires. "For every 10°F change, your tire pressure changes one pound per square inch (psi). As the tire deflates, the sidewalls of the tire begin to collapse and build up heat as the tire rotates." Too much heat can cause a blowout, which is both costly and dangerous.
As for the battery, "In cold weather it takes more energy to start that engine. The oil is cooler, the component inside have much more resistance to move so the start is going to draw more current off the battery. So it will be more difficult to start it when it's cold than when it's warm, warns Reinarts.
He recommends replacing the battery every five years. Reinarts also advises drivers to make sure it's a good quality battery and big enough for your vehicle.
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