What Does Sugar Do in a Car's Gas Tank?

Can adding sugar to a fuel tank destroy your engine?

There is a popular misconception that the addition of sugar to a gas tank can ultimately lead to permanent engine failure. In truth, sugar does little damage, and recent scientific developments even suggest it could be used as a fuel of the future.

The Theory

It has long been argued that sugar, once added to a fuel tank, will dissolve and circulate around the engine. In turn, the heat generated supposedly converts the sugar into a porous sludge that solidifies once the engine cools down into a cement-like residue that ultimately causes the engine to fail.

The Reality

In 1994, Jim Thornton, a forensics professor at Berkeley, carried out a series of tests that ultimately proved sugar can only dissolve in gasoline in minutely small quantities. Any sugar added to a tank would stay in the same state, and this would make it difficult to circulate. Indeed, the filter systems used in most motor vehicles would prevent the mass movement of sugar anyway. However, sugar can cause filters and injectors to become blocked.

Resolution

If sugar does find a way into a fuel tank, whether maliciously or accidentally, it still needs to be removed. Dropping the tank, emptying out the old fuel and changing the filters and injectors is a relatively inexpensive operation that will help prevent further problems.

References

• Snopes: Sweet Revenge