The Associated Press has learned the engine in Matt Kenseth's race-winning car from Kansas failed inspection at NASCAR's Research and Development Center.
NASCAR officials were discussing Wednesday what penalties to levy against Kenseth and Joe Gibbs Racing, multiple people familiar with the inspection told the AP on the condition of anonymity because no decision has been made.
The engine failed because one of the connecting rods not meeting the minimum weight requirement.
Kenseth drove the No. 20 Toyota to his second win of the season Sunday in Kansas. It is standard procedure for the race winning engine to go back to Concord for a thorough inspection.
The JGR engines are supplied by Toyota Racing Development out of Costa Mesa, Calif., but NASCAR would hold the team responsible for any infractions.