1972 MAZDA Piston Engine Modification: Description

The exhaust emission control system on all except 808 models consists of a throttle opener, which controls throttle during deceleration; an ignition control system, which regulates advance and retard of ignition; and a slow fuel cut valve, which prevents dieseling when ignition is turned off. 808 models, with manual transmission, use only the throttle positioner, while 808 automatic transmission California cars use a throttle positioner and a vacuum switch connected to intake manifold. Non-California 808 automatic transmission models require no special equipment to meet exhaust emission regulations.