A system and method for improving performance and fuel efficiency of a combustion engine by providing an oxygen enriched gel which is inserted near an air intake, where the gel is stored within a container formed from a gas permeable membrane which is sufficiently porous so as to enable the gel to gradually evaporate. The evaporating gel releases oxygen, which is drawn into the air intake, resulting in reduced emissions and improved performance of the engine. No modifications to the combustion engine are required to use the system. The gel is inexpensive, and the gel container is preferably replaced or refilled approximately as often as an oil change is performed.