S4E17 · Hills of Fire

Michael and K.I.T.T. have the seemingly easy, relaxing job of patrolling a national park for a couple of days, when they find themselves up against an arsonist driving an All-Terrain Vehicle, who escapes over rough terrain that K.I.T.T. can't cover. As they investigate to find just who is behind the spate of arson attacks, Michael must prove the innocence of a teenage boy, a reformed vandal, who is being framed for starting the fires...