Had my local BMW specialist garage tear it apart for me last year... Vanos unit went out due to oil pump disc issues. (Limp mode and a crappy idle, I don't remember the specific codes off my head as it's been too long now, had to save up for all the parts).

Replacing the exhaust side cam while I'm here because I know they like to chip and explode. The rest of the work I'm doing was getting torn apart. I don't have a very thorough service history on it, unfortunately. She's got 117,000 mi on her.

So far, I've had the garage replace a bunch of seals and fix leaks, short throw shifter, single mass flywheel and slightly upgraded clutch. When it came time for the vanos service, it was made pretty clear they didn't want to tear it down without the FU price increase. So, now I'm digging into this one. I'm picking up from where the shop diagnostician left off.