Its happened 3 times in the last 2 months, but never before in 17 years. Both the car and the weather were hot each time, but that's nothing new. There was one incident during cold weather in spring 2015 when it refused to start from cold, it was just cranking with no compression evident, which an AA man overcame by churning the motor on full throttle and diagnosed a sticking air flow valve or sensor. My service agent could find nothing wrong. It has not happened again.