Throttle Opener System
During periods of deceleration, the air/fuel mixture entering the engine is not sufficient for normal combustion. The system uses intake manifold vacuum during these periods to slightly open the primary throttle valve in these periods to slightly open the primary throttle valve in the coasting condition (to an opening of 1400 ± 100 RPM, unloaded). The optimum amount of mixture is then fed to the engine to continue proper combustion.