[mjau]

Car: E90 318d 2008 2.0D 100KW
Issue: won't start
Video1: https://www.youtube.com/shorts/e4O0T1zpJhs
Video2: https://www.youtube.com/shorts/yw1RJYXTfTc

History with this issue:
20.04. drove ~30km - all ok
20.04. same day after an hour - tried to start, won't start (see video2). Tried to push it from the hill, second key, no luck.
22.04. tried to start it, car starts!
24.04. car starts, 2 trips (total 50km), all ok
28.04. car starts, 3 trips (total 100km), all ok
03.05. car won't start
15.05. car won't start
16.05. tried with a battery pack (mechanic1), another vehicle with cables(mechanic2), car won't start
17.05. car won't start, tow truck takes it to the shop
22.05. got it back from the shop - car works, they did nothing to it because it is working, nothing to diagnose... I drove home and started few times, all works without issues
23.05. car won't start (see video1)

Tried:
- push, start from battery pack, start from another car, second key - no luck
- fuel is correct, as you see above, I was able to drive before / during / after the issue appeared

What could be the issue? Doesn't make any sense why does it randomly starts working. Could it be crankshaft speed sensor ?

Or maybe it has something to do with heating / cooling ? I topped up cooling in January, that was the only thing done to car this year. Usually it gets pretty hot here in Spain, but recently it is much more mild and tonight (+16°) it still won't start. I even tried to start the car with driver seat doors open because that's how it was done in the shop, but still won't start.

[phils2]

Any fault codes?
Starter relay?
Had this with an Audi A4.
Removed and refitted every fuse and relay and it worked.