The qualifying times of Austin Dillon and Daniel Hemric were both thrown out after both cars were found with unapproved alternators at Michigan International Speedway.
Dillon has qualified seventh while Hemric was 11th fastest in qualifying for the Consumers Energy 400.
In addition, each crew chief will be fined $25,000 and 10 points will be deducted from the driver and owner standings for each team.
The penalty will move both cars to the back row of Sunday’s race.
Dillon was the fastest in the first practice session at the 2-mile Michigan track. Hemric was fifth on the speed chart for the opening session.