Sandstorm lives for action.  His only real fear is a fear of boredom.  As a result, he takes unnecessary risks, both in combat and out - risks that can sometimes threaten the success of his mission.  He lives fast, loud and dangerously - traits that make him fun to hang out with mos of the time.  But his felow Autobots are getting a little sick of his habit of giving away his position to the Decepticons just so he has the opportunity to enjoy a fight.