Question: In 1955 when Doc and Marty are in the outdoor cinema and Marty is accelerating to 88mph to jump back in time to 1885, doc shouts something to him in celebration as Marty Drives past him, he also fires his gun in the air... Do you know what he shouts? The subtitles just say "shouts something in Spanish" but id love to know what he said and what it means?
Question: Doc Brown shows up at the end of part three with his wife Clara, his two boys, and a time-traveling, hovercraft-converted train. How did he build it? There was nothing in 1885 that could even begin to help him build another time-machine! And don't tell me that he used Marty's 'hoverboard' as parts, because that doesn't wash.
Question: Why does everyone say that using parts of the DeLorean that Doc had buried in the abandoned mine could create a time paradox? Firstly, that is never stated in the actual movie. Secondly, if say Marty and Doc use the part on the buried DeLorean to fix the DeLorean that broke due to the explosion caused by the extremely strong alcohol and then again try to run the DeLorean using alcohol that's not so strong, the 1955 Doc would be able to obtain the missing piece of the buried DeLorean. So, technically, there's a plot hole. Why then does everyone say that that's not possible?
Question: When they discover they have no gasoline for the DeLorean, they go through all sorts of trouble to get it up to 88mph. Now it's obvious things fade away and into existence in this movie, as it did with the newspapers and matchbook. Wouldn't it have made more sense to go to the mine where the time machine was buried and write on the wood, "Bring can of gas"? Wouldn't a can of gas then materialize in the trunk of the DeLorean and they could go home?
Question: Why did Clara go mental at Doc for saying he was from the future? He'd dropped a few hints! He'd told her he has an interest in science, he had a huge refrigerator in his building, he had another big thing covered up under a sheet, he said he read Jules Verne when he was a boy despite it only been recently published. Was she not even a little bit curious? Doc could have easily stopped her during her rant saying he can prove it but didn't.
Question: Doc gets Marty back home. Then seconds later Marty appears again. He shows Doc the letter he wrote. So Marty goes back to 1885 to save him. They make a big deal of having to repair the DeLorean that was buried in the cave. But why can't they use the DeLorean that Marty just used to get back to 1955?
Question: Marty tells Doc that they are out of fuel as the fuel line ripped on the car. Wouldn't it have made more sense for them to uncover the DeLorean that Doc buried, put a piece of paper on the seat with a note saying something like... "Oh Marty, I forgot to mention in my letter that the car needs some extra fuel. Keep a can of gas with you in the car at all times" - Hey presto, Marty would have arrived with extra fuel! Now obviously I hear you shouting "continuity" and "It would be an alternate timeline like in part 2" - But that didn't stop Biff taking the car back to the 2015 Doc and Marty were in, despite Doc later saying if they travelled into the future it would be the rich Biff reality.
Question: How did the new gauge in the car read the boiler temperature? It wasn't connected to the train at all.