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Deceleration Control System: Description

The Deceleration Control System is designed to maintain a balanced air/fuel mixture during deceleration. Upon initial deceleration, rapid closing of throttle plates can cause overly rich fuel mixture. This system consists of an anti-afterburn valve (air by-pass valve on 626 and Calif. B2000) and throttle positioner system (except Federal GLC and Calif. GLC with Man. Trans.). Throttle positioner system consists of servo diaphragm, engine speed switch and 3-way solenoid valve. The air by-pass valve (626 and Calif. B2000), part of the air pump type air injection system, functions during deceleration to assist in emission control.

Fig 1: Showing Air Flow Through Anti-Afterburn Valve
G09324553Courtesy of MAZDA MOTORS CORP.