Valve stem body failed during tire inflation. it is not possible to inflate tire to spec. possible rapid air pressure loss while driving. bmw of san francisco refused to repair under existing manufactured warranty.
Tire pressure monitor signals low air pressure every week on instrumentation. run-flat tires lose air weekly. tire has to be topped-up with air then tire pressure monitor test performed. owned vehicle since february, 2016 and frequent, annoying, embarrasing tire air filling has to be done weekly.