My car was having unstable and irregular idle, plus loosing power when driving or riding like new, absolutely impossible to produce/simulate the default.

See my post "loss of power while running"

I realised that there is a very complex vacuum management system. I thought my problem could be vaccum related, then I started changing these valves (which fortunately are cheap), the hoses to the Idle control valve as well.
Now I have a very smooth idle, less stalling but the problem is so erratic that I do not dare to say that it is over.