Early Fuel Evaporation ( EFE ): Testing and Inspection

VACUUM OPERATED EFE VALVE FUNCTIONAL CHECK

For electrical diagnosis of Solenoid Operated Type systems, refer to EFE diagnosis charts in ``Computer Command Control (C3)'' or Electronic Fuel Injection'' section.
1. Note position of actuator arm of EFE valve with engine off, then start engine and observe EFE valve movement.
2. When engine is started cold, the valve should close, pulling the actuator link into the diaphragm housing.
3. If valve does not close, stop engine and disconnect vacuum line from EFE valve.
4. Apply 10 inches Hg vacuum load to EFE valve and note position of valve. Valve should be closed and remain closed for approximately 20 seconds without applying additional vacuum. If leak-down time is less than specified, replace EFE valve.
5. If valve does not close it may be seized. Lubricate valve with heat valve lubricant and recheck. If valve remains open, it is defective and should be replaced.
6. If valve is closed and problem continues, check for pinched, loose, kinked or plugged vacuum hoses. Repair or replace as necessary.
7. Run engine and allow to reach normal operating temperature. Valve should be open.
8. If valve does not open, remove vacuum hose from EFE valve and check if it opens. If valve opens there is no air bleed for the valve diaphragm, the TVS or EFE solenoid plunger is stuck in the cold mode, or the engine is not reaching normal operating temperature. Check and replace thermostat, TVS or EFE solenoid, if defective.

CERAMIC HEATER GRID SYSTEM CHECK

Refer to ``EFE Operational Check'' in ``Computer Command Control (C3) System'' or ``Electronic Fuel Injection'' diagnosis section.