Early Fuel Evaporation ( EFE ): Description and Operation

EFE System:

The Early Fuel Evaporation (EFE) System heats the incoming air/fuel mixture to improve atomization during cold start and engine warm-up. This improves driveability and reduces HC emissions.

The ECM controlled system consists of a relay, coolant temperature sensor and EFE heater. When coolant temperature is below specification, the ECM will energize the relay, supplying current to the EFE heater. When coolant warms to near operating temperature (approx. 65 - 75°C / 150 - 160°F), the ECM will de-energize the system.