My 2001 Series 1 with approx 16k miles has had intermittent issues with the solenoid 'clicking'. Various specialists have opined on it with general consensus being a slightly low battery charge. This kind of makes sense as after I top-up the charge the issue resolves itself. Stopped happening for quite a number of months, then reappeared
I have been known to put the car into gear and give it a 'rock' back and forth to move the flywheel.....and that has helped also.
