Dale Earnhardt Jr. ran 11 laps in Wednesday's opening practice before the engine in his No. 88 Hendrick Motorsports Chevrolet SS expired.
Because of the subsequent engine change, Earnhardt will start from the rear of the field in Thursday's first Budweiser Duel 150-mile qualifying race.
"I don't know what happened," Earnhardt said of the engine failure. "We'll just start at the back of the qualifier (Thursday) and try to race up through there."