What if I put sugar in someone's gas tank?

By: Katherine Neer  | 

Pouring sugar into someone's gas tank is rumored to ruin their car. Will it really?
Pouring sugar into someone's gas tank is rumored to ruin their car. Will it really?
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­For some reason, there's a common rumor about sugar and gas that's been around for decades. Supposedly, if you pour sugar into someone's gas tank, you will disable the car. The sugar is supposed to react with the gasoline and turn into a semi-solid, gooey substance that totally clogs up the gas tank, the fuel lines, and so on.­

It sounds great, especially if you have a grudge against someone. The problem with this rumor is that it simply isn't true. As it turns out, sugar doesn't dissolve in gasoline. Pouring sand into the gas tank would have about the same effect as pouring in sugar. The sand or sugar might clog up the filter, and that could disable the car, but it's not a sure thing.


So what do you do if you really do want to disable someone's car? Pour in some water. Gasoline floats on top of water, so if you pour in several cups of water, the fuel pump will fill the fuel lines with water instead of gasoline and the car would have some major problems.

Originally Published: Jan 24, 2008

Sugar Gas Tank FAQ

What does putting sugar in a gas tank do?
It is believed that when sugar is put into a gas tank, it reacts with the gasoline and turns into a semi-solid substance that clogs the fuel lines.
How would you know if someone put sugar in your gas tank?
There are a few signs of sugar in a gas tank. For instance, you may notice a power surge while accelerating or even fuel pump failure. Other indicators of the presence of sugar in the gas tank are poor vehicle performance and an engine that stalls. 
Can sugar in a gas tank ruin an engine?
When sugar is poured into a gas tank, it eventually makes its way into the engine where the sugar dissolves and caramelizes. This sticky, semi-solid substance then sticks to the engine's components and ruins it.
How much sugar can ruin a gas tank?
It is estimated that less than a teaspoon full of sugar per 15 gallons of gas could result in engine issues. However, the effects are worse if there's less gas in the tank.
How much does it cost to get sugar out of a gas tank?
A mechanic is the only one who will be able to remove the sugar. For that, the gas tank will need to be removed and thoroughly cleaned, which can cost hundreds of dollars. Stop driving your vehicle immediately and call your local mechanic to get a quote if you’re having this issue.