Thanks Dave. Just bog standard unleaded. The car has never been privileged to have anything else
In that case seems like it may well be a slip ring noise
Yes, the gauge is on a bit past midway (10-16v) once 'up' so that something just over 13.5 v, or so . It only takes say 15 or so seconds to get get there. The volymeter is out of an old Yazaki cluster that I found was an exact fit for the VDO on the car. No flickering from the charge warning light
