Factual error: When Ethan is driving through Texas while Peter is sleeping; the camera shows a Texas Highway traffic marker that reads: "Dallas 36 Miles." In the same camera shot, we see mountainous terrain in the background; followed by additional camera shots that show more mountainous terrain as they travel on the highway before crashing off the overpass. The problem is that there is no mountainous terrain 36 miles outside of Dallas, Texas; it's pretty much flatland.
Factual error: In the scene where Peter & Ethan are traveling across Texas on I-120 the train reads Union Pacific, but Burlington Northern Santa Fe (BNSF) is the one that runs that track.
Continuity mistake: Near the end of the movie, Ethan tells Peter that he had his wallet all along. Peter steps forward from the car wearing his glasses. In the very next shot, they are gone and nowhere to be seen.
Continuity mistake: In the scene where Peter (Robert Downey, Jr.) is drinking the energy drink in the petrol station, the angle of the bottle changes. From the profile shot, the label can be seen with the brand visible, but cut to the front-view and you can see that the bottle has completely shifted angles.