We have been having issues with our enclave shutting off while driving with no warning. Most of the time it will start back up when turned off and restarted but sometimes it will take 20 minutes to restart up to hours before restarting. We have replaced the relay starter and purge valve and worked great for a while then started doing same thing again... shutting off randomly with no warning. Anyone have similar problems or know of this issue? Just had it at the mechanics for two weeks and was told they cannot figure it out and had the battery charged up and working fine for him but the first time we take it out to the store it does it again right away!