Matt Kenseth faces possible sanctions after his winning car's engine failed a postrace inspection after the Sprint Cup race last Sunday at Kansas Speedway.
According to multiple reports, Kenseth's car did not pass a secondary inspection after at NASCAR's Research and Development Center in Corcord, N.C. The car had made it through an initial inspection at the track after the race.
The problem apparently was with the weight of one of the eight connecting rods not meeting minimum weight requirements.
Kenseth drives for Joe Gibbs Racing, whose engines are developed by Toyota. The win at Kansas was his second victory of the season in the series.
NASCAR was discussing possible penalties against Kenseth and his team on Wednesday, ESPN.com reported.
Two weeks ago, Sprint Cup drivers Brad Keselowski and Joey Logano were stripped of 25 points each because of problems with the rear housing of their Penske Racing cars before the NRA 500 at Texas Motor Speedway.