So, the intermitent overboosting was due to a sticking turbo solenoid. Sometimes would underboost too. I had a used one laying in the garage and fitted it and now it's OKish. Sometimes I get hesitation and what feels like throttle modulation when flooring it between 3k and 4k rpm. Probably the wastegate needs adjustment

Too high fuel pressure: this was easy, but difficult to find. Previous owner wired the pump earth directly to the chassis, bypassing the PEM. The PEM was faulty, but hopefully I had one that was working fine. Fuel pump was replaced in 2015 and still goes strong, so problem solved.

The bi-xenon solenoid failure was the position sensor inside the headlamp. I just fiddled a bit with the cable and now's working. The headling height adjustment was due to a blown fuse. The headlamp height motors use the same fuse as the headlight wipers. I had a seized headlight wiper that was blowing the fuse, so I went to the scrapyrd and 35€ and one fuse later everything was working fine.

Things I'd like to do before christmas:

1. Downpipe, swapping the original broken cat with a 200cell sports cat. I'm currently running a second downpipe

2. Sort the interior, torn leather on the driver's seat, filth, broken auto dimming mirror...

3. Currently waiting for my TME spring set

4. Subframe bushings, still undecided: XC90 or solid?