Just bought 2014 Murano and took to long drive. there was a burnt smell? why?

Burnt smells can come from oil or cleaner burning off on the exhaust or an electrical short. Maybe the seller did some engine cleaning and it's burning off on the exhaust. Since the this vehicle is so new, there may not be data available to RepairPal to support it or it could be an error on their part. I'll pass along your concern for the 2014 Nissan Murano not listed.