Continuity: Sgt.King has a wound above is right eye and Michelle helps him take care of it in the Motel. A few minutes after when Steve arrives to meet them in the motel the wound changed place and is now above Sgt.King's left eye.
Continuity: When Sgt. King steals Steve's jeep the top is down. Sgt. King is in a hurry, yet when he shows up at his destination in the next shot, the top of the jeep is up. Jeep tops take at least 10 minuets of tedious work to put up, and it was sunny all day, so it could not have been put up due to rain.
Errors in geography: When driving to D.C. they cross a huge bridge over a major ocean port. If they are in west-central Texas as is implied, they would not cross any major ocean port bridge early on in the trip. It would be way out of their way to go to Houston.
Errors made by characters (possibly deliberate errors by the filmmakers): During the Humvee-car chase sequence at the beginning of the film the character "Rico" has no ammo magazine in his rifle during the whole scene.