History (this is number 3):
idle went to hell. rattles. shaft moves a bit in/out very distinct gap around butterfly
Installation: idle perfect. don't know if rattled. no shaft movement. no gap around butterfly
Now: same as first. (bad idle, rattles, shaft moves, butterfly gap).
same as second at installation (no rattle) and presumably same as first when brand new.
So why the post? I only noticed the rattle in 1st+2nd recently when reinspecting before ordering the 3rd.
Strong suspicion that the rattle is something on the end of the shaft that is hidden behind the ecu that broke / came off (eg a nut worked itself loose) and since the return spring on the shaft has a slight outward pressure* this led to the shafting pushing outwards so the butterfly rubs against the side of the barrel giving very visible wear / gap.
So why the rattle? Was there missing loctite on the nut on the hidden end of the shaft? was there a plastic thingy that cracked and broke in there? Was the 60C air temp reported by the ecu for long periods related to this failure?
So ... the new one is slightly different. Previous were both 32M4/B and this new one is 32M4/C which I interpret as a hardware revision. Definitely a different cast mould (see pic). Also this one came with a white silicon/rubber cover of the ecu (have seen this on pics of other peoples hpe). Might be more robust if I'm lucky.
I'm currently a bit scared to install the new until I mount a fan in the engine bay. I am also currently testing a crude bracket to keep inwards pressure on the shaft on the 2nd
* I know the spring has outward pressure as I dismantled this part of the first.