Vacuum Servo EFE System

Fig. 41 Vacuum servo EFE valve. W/integral actuator:

Fig. 42 Vacuum servo EFE valve. W/remote actuator:

This system uses a vacuum servo operated heat riser valve, Figs. 41 and 42, to increase flow of exhaust gasses through the intake manifold passage during cold engine operation. Control signals to the vacuum servo are controlled by a thermo vacuum switch (EFE-TVS) on all except some models equipped with the C-3 fuel control system. On these models, vacuum signals are controlled by the C-3 system computer through a solenoid operated vacuum valve (EFE-SOL).