This movie actually made me mad because of the character's logic.
They couldn't make a SINGLE rational decision the entire movie.
For starters, why are the characters always approaching the house that Leatherface is in, knowing that he is in there? The Texan guy just got into the house carelessly like nothing bad can happen to him, guess what? He fucking died. And their decision to not call the police was probably the stupidest thing to do, they literally saw a man with his face slashed and they decided to chill on their bus instead of driving away to get help. And even worse than that, they didn't even call the police in the first place. Even though the Texan guy clearly told this girl to call the cops. She just went back to the bus and did absolutely nothing about it. The best thing to do is to drive away and alert authorities. Because being close to the danger doesn't help the people that are in danger, it just endangers more people.
Now, do you remember Sally from the first movie? The one that ran away. She came back to kill him and get her revenge. Now the main problem with that is that she does everything wrong in the process of attempting to kill him. She dealt with him once already, then why the fuck are you making the stupidest mistakes possible. First of all, you can see she goes inside the fucking house. WHY?
Why the fuck would you go inside the house, lure him outside. This is clearly the right thing to do in the situation. It was already established that he gets lured by noise and he will get outside of the house. And it's much much easier to deal with him in the open space instead of in a cramped house. Because you have a gun you can get far away and get a clear advantage. Because Leatherface is a very physically strong individual your chance of winning him over in a small apartment is heavily reduced. Lure him outside and deal with him this way.
After that Sally gives the main characters that have the strongest plot armor I've seen in a while the car keys. So obviously the right thing to do is to drive away and get help, right? Well, they do not think so.
Instead, they try to crush Leatherface with this lame, slow piece of junk (AKA Sally's car). He is already busy with Sally, so why deal with him? It will only have negative results.
Of course, they weren't able to perform vehicle manslaughter on Leatherface… he has a fucking chainsaw. He could easily harm a vital part of the car before getting harmed. Let's assume they were able to run over him with the car, he already proved that he has incredible sturdiness and can withstand a lot of things. So he has a pretty high chance to be alive after being run over by this slow car. AND because he has a chainsaw he could easily harm a vital part and cause the car to stop working. So now you are stuck with the car not working and Leatherface still being alive. Great situation to be in.
There were many more illogical decisions made by the characters because I only watched it once and can't recall all the stupid decisions made by the characters. But yeah, the only reason one person got alive is coincidences over coincidences.