Hall of Fame Racing's No. 96 Toyota was held in the inspection bay at Chicagoland Speedway by NASCAR officials until shortly before the start of Saturday night's LifeLock.com 400.
The car failed pre-race inspection when two water bottles were found in the car containing lead, NASCAR officials said.
Driver J.J. Yeley was allowed to join the field after the 42 other cars had already started the pace laps and then was required to serve a stop-and-go penalty on pit road after taking the green flag.
Any additional penalties for the infraction will be announced next week, NASCAR officials said.