As I noted in one of my earlier posts, after securing this valve in both positions manualy, I still get the rattle. Just not as loud.
The valve is simple to remove, but you can pretty much only remove and inspect it. You will require a Torx bit for the three screws and you need to remove the clip that retains the Bosch plug on the coil at the base.
NB: You may need to remove some of the inner guard covers just to provide enough room to withraw the valve from the manifold. This is easily achieved.
It is a sealed unit, therefore you cannot replace any of it's components. My valve had a worn butterfly linkage, this allowed the butterfly to be riggled in both positions. It also had a torn seal on the vacuum side, this allows the manifold vacuum to pull on the valve's main operating diaphragm.
The unit for my 318 with an M43 engine here in Australia costs $315.15 (Part No. 11611438404).
PS: I have cleaned and checked the PVC valve (this mounts directly above the Disa and a little toward the rear of the engine), this had no effect on the rattle.
I hope this helps you out. I will keep posting any news.