The plate is part of something that looks like a teeter-toter (sp?). When one side lifts, the other permits a smooth metal pin to slide down - I suspect the metal pin/rod is no longer perfectly smooth. Could be gunk, could be a smidgeon of rust.
Years ago, I unbolted the distributor, and after some fiddling, was able to make the pin come out. There was an area of a rust stain - some good polishing, and it was smooth as new - and working the way it was supposed to.
This was on a K-Jetronic.

__________________
It is a truism that almost any sect, cult, or religion will legislate its creed into law if it acquires the political power to do so. Robert A. Heinlein


09 Jetta TDI
1985 300D