Early Fuel Evaporation ( EFE ): Testing and Inspection

Fig. 036 - Wiring Diagram for Chart C-9D Electric EFE Non-ECM Controlled. VIN 1, VIN C, VIN G, VIN L, VIN X, VIN Z:

CHART C-9D, EFE CIRCUIT CHECK

When engine is cold the heater switch is closed allowing current to flow to grid with ignition on. The grid is located under the carburetor and is used to help vaporize the fuel on a cold engine. When the heater switch reaches its calibrated valve the switch opens and the circuit opens.

Fig. 035 - Chart C-9D Electric EFE Non-ECM Controlled:

1. Back probing the heater switch checks for voltage to the switch and checks continuity of switch.
2. Checks wire between heater switch and grid connector.
3. Checks the heater grid ground connection.
4. Test should be peformed with an ohmmeter, and if over 3 ohms the grid will not heat up sufficiently. Therefore, the heater grid should be replaced.
5. Checks to see if heater switch is opening when engine warms up.