From Jayski.com:

 Joe Gibbs Racings Nationwide Series teams will be penalized for attempting to manipulate the throttle so NASCAR would not get a true horsepower reading when putting their cars on the chassis dynamometer following the Carfax 250 at Michigan International Speedway, NASCAR spokesman Jim Hunter said Saturday night. Both the #18 and #20 teams face penalties for what was a blatant attempt to interfere with the inspection process, Hunter said. What they did was not in effect during the race, Hunter said. They didnt have an illegal part or engine during the race. They tried to do something involving a magnet so that we wouldnt get a true reading on the dyno.(SceneDaily.com)(8-17-2008)


UPDATE: Joe Gibbs has issued the following statement: "If this alleged incident proves true, it goes against everything we stand for as an organization. We will take full responsibility and accept any penalties NASCAR levies against us. We will also investigate internally how this incident took place and who was involved and make whatever decisions are necessary to ensure that this kind of situation never happens again. The expectations we set for everyone at Joe Gibbs Racing begins with me, and I personally apologize to NASCAR, our partners and our fans for the negative light this situation has cast upon all of us."(Joe Gibbs Racing PR)(8-17-2008)