Near the beginning of the movie, when "Alfredo" takes the girl's picture, the position of his hands changes several times when he is holding the photographer of her.
The painkillers Benny gives Michelle and Ryan take effect almost instantly and then wear off in about five minutes.
At the climax, the chainsaw falls into a small lake/body pit and slowly begins to sink. First of all, the chainsaw's weight would have caused it to sink almost immediately, not slowly. Secondly, somehow the chainsaw continues running despite the fact that no one is giving it gas and it is partially submerged in water.
This movie supposedly takes place out in the middle of nowhere, miles away from anybody, but numerous times throughout the movie lights from houses are visible in the background.
In all of the early video editions, at the very end of the movie when Michelle closes the truck door after Benny gets in, the sound of the door slamming shut is heard before the door actually closes. This has been corrected in the recently reissued version however.
When Michelle and Tex are at the gas station standing in front of the car talking, the camera crew is reflected on the grill of the car.
While supposedly set in Texas (a plains state) the California mountains are frequently visible in the background.
Towards the beginning of the film, a character says they're about "three hours from Houston" while in a very arid desert. There are no deserts within a three hour radius from Houston, which is instead surrounded by thick piney woodlands, flat farmland, and the Gulf Of Mexico to the south. The closest desert to Houston is nearly 10 hours west of the city.
Near the beginning of the film, Ryan mocks the radio broadcaster for being unable to pronounce "adipocere" while also failing to pronounce the word correctly.