This latter function is necessary to prevent one form of vapor lock: a stoppage of fuel flow caused by an insufficient amount of atmospheric pressure inside the tank.

特别要防止汽油收缩时，由于油箱内的大气压力不足导致供油中断。

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If, on the other hand, you were to buy summer gasoline and try to store it until winter, you might find yourself having problems getting the fuel to ignite, due to the lower vapor pressure.

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