The "white thing" is the vacuum control valve for the transmission. It reduces the vacuum level by leaking. The higher the "throttle" position,l the greater the leak. The valve has nothing to do with the IP, it is located there because it needs to be connected to the accelerator linkage. The buzzing sound is normal. It continues after engine shutdown because of residual vacuum in the system. The "green thing" is nothing but a damper to eliminate rapid vacuum changes to the transmission modulator.