Early Fuel Evaporation System: Description

The Early Fuel Evaporation (EFE) is used to provide heat to engine induction system during cold driveaway. Two EFE systems are used on General Motors vehicles. Engines may be equipped with either a vacuum servo type, or an electrically heated type EFE system.

Both vacuum servo and electrically heated systems provide rapid engine warming. Results are faster fuel evaporation, more uniform fuel distribution, faster choke opening and reduced emissions.