Exhaust Gas RECIRCULATION: Operation
Exhaust gases flow out of exhaust manifold, through EGR tubes and into EGR control valve(s). The EGR control valve(s) controls EGR flow in response to vacuum signals received from the vacuum amplifier. The vacuum amplifier monitors carburetor ported vacuum and controls vacuum applied at EGR control valve(s). The water thermo valve, water thermo switch (626 models), solenoid valve(s) and speed switch (if equipped) allow recirculation of exhaust gases under various engine operating conditions.
NOTE:
Refer to "Mazda Piston Engine Vacuum Diagrams" article in this section for components used by model application.