Firing up my E31 BMW 850 during the winter hiatus. I advise you to crank up the speakers a bit and, if you are impatient, turn on notifications.
The rough idle at first is due to a slight issue with the intake gaskets when cold – first 15-30 sec i have to hold it on the throttle so i’m sure it doesn’t die, you can hear it struggle cranking due to the batteries being depleted. Didn’t want to risk having to do it again. The problem is almost non-existent in the summer, and it’s a ~5k USD job, so it’s been put off. But a complete engine rebuild (custom 6.0 bottom end) is going in this summer so it’ll all be good!