Safety issue with tire pressure monitoring system (tpms). sudden loss of air in tire at high speed. pressure monitoring valve had disintegrated and fallen into tire, we learned, causing immediate flat tire. corrosion, we were told. car had less than 41,000 miles on it, and had been maintained at prescribed intervals, and we were not warned that this problem could occur. we narrowly avoided an accident in heavy traffic at highway speeds. this is a significant safety issue.