The sales success of the 2005 Ford Mustang is chugging along, but it appears as if the outgoing Mustang has some skeletons in its closet that are being brought to light by an NHTSA investigation. The Car Connection reports that model year 2003-2004 Mustangs and Mustang convertibles are being looked at for a potential problem that involves the carpet interfering with the motion of the accelerator pedal. The Associated Press has revealed that seven people have complained about this and 20,000 units could be affected. The issue has not, however, reached recall status, which, even if it did, probably wouldn't affect the incredible sales momentum of the 2005 model since it's basically an all-new car. Just to be safe, owners of the 2005 model may want to groom their carpets a bit.