After vehicle sits in hot sunlight for extended period of time, and ac is ran-- there is a loud "popping noise" from the center area of the dash. The sound is very similar to a rock or object hitting the windshield. This issue has continued and recently took vehicle in for other recall issue and had them check this. The service adviser first told me they duplicated the issue and would have to dismantled the dash for further diagnostics. The vehicle was in the shop for over a week, and they told me the issue seemed corrected. The completed service ticket indicates problem could not be duplicated or determined. The day I drove home from the shop the vehicle made this same noise three times. I will be taking vehicle to different GM dealer for follow up.

- Edmond, OK, USA