There is a fitting on the intake manifold that provides a boost signal to the ALDA and the transmission vacuum amplifier. When you removed the ALDA, what did you do with the spur that feeds the ALDA? Ideally you capped it or replaced the splitter with a straight fitting to connect to the vacuum amplifier. Confirm this before you touch the Bowden cable, VCV or transmission modulator.

Sixto
87 300D