Static ignition timing

[Robou]

While driving through eastern Europe the knock sensor was very busy. Sometimes the petrol didn't even smell like petrol. Luckily I have an easy way to reset the ECU. On the way back in Germany I could fill the car up with 100 RON. It made me wonder if there would be a smart way to change the ignition timing under moderate load in order to adept to these discrepencies in gasoline quality.

I stumbled upon the fact, that Bosch made a prevision in most of the older EZXXXK's, it is called selector switch or the like. By manipulating these a kind of change in static timing can be achieved. In our EZ210K pins 18 and 19 are connected to a circuit which could very well be meant to have this effect, anyway, I see no specific use for it. In diagrams I see the pins are left out.

When opening the terminal connector to the EZ210K I found a yellow/red and a yellow/black wire connected to the pins. There was no obvious connection point of the wires in the car.

Chances are, they're meant to be connected to ground through a switch, because they have a pull-up resistor on the PCB. Furthermore, they could be meant as a servicepoint to adjust the static ignition timing to the gasoline used. Even more, if the program in the controller permits, it would come very handy to adjust timing on the fly.

On the forum I read a lot of people are struggling with looms. Could anyone tell where these wires are supposed to connect to? Because, if they are already used for some purpose, the dream won't come true.