Take This Quiz To Find Out If You’re A Car Engine Expert!

How much fuel is left over after the combustion process?

Retry Correct Incorrect Not all of the fuel is completely consumed by the combustion process. Afterward, a small amount of fuel will still be present, and some of it reacts to form oxygenates, including formaldehyde and acetaldehyde.

Next

Maja Hitij/Getty Images

Maja Hitij/Getty Images

How much fuel is left over after the combustion process?

• All of it
• None
• A small amount
• Most of it