Dry gas

Dry gas is an alcohol-based additive used in automobiles to prevent any water in the fuel from freezing and to restore combustive power to gasoline spoiled by water. It is added to the fuel tank and binds to the water to burn it off.[1] Dry gas typically contains either methanol or isopropyl alcohol.[1]

Most gasoline now contains around 10-15% ethanol solution.[2] Current gasoline-powered automobiles can safely run-up to a 10% ethanol solution without modification. However, at 15% or above, older vehicles may require replacing the fuel lines to prevent degradation and rupture.[2] In this case, the electric fuel pump may also need modification to prevent ethanol "dry rot".

The belief that dry gas ¨Is not needed¨ because of the significant amount of ethanol present in fuel is mostly true; Ethanol is a drying agent that has an affinity for water present in the atmosphere. It binds to the moisture in the fuel tank, which reduces issues with freezing fuel lines. Adding dry gas lowers the freezing point of the water and alcohol mixture to lower levels than what ethanol can produce. causing fuel lines to become freeze resistant.