Read all the stickies, funktionsrahmen and s4wiki until you understand them and they're not just gibberish.
It's anything but an easy task if you have no to little experience tuning and working with cars,
and the learning curve is very steep.
If you understand German, that's a big plus
Unfortunately I do not understand German, have been trying to read s4wik. I am from the distant continent, the future for a long time like you learn, there may be some problems in language communication.
