I sure hope these are just rumors that never come to fruition. Autopia is one of the oldest and most classic rides in Disneyland, one of the top rides that always come to mind when people bring up Disneyland.
Autopia was put in Tomorrowland because it represented the part of Walt's dedication speech saying "...here youth may savor the challenge and promise of the future." It is meant for children to enjoy the joys of driving, something they won't actually be able to do usually for another decade or more. Autopia also gave parents time to relax while kids drove, to have fun with their children together, or to drive one alone and become a child themselves.
I agree that Autopia needs an update, as does all of Tomorrowland (which when looking at the attractions there today should really now be referred to as Sci-Fi Land since the only part of the entire land that even broaches the subject of our actual future is the Home of the Future in Innoventions). The gas fumes and breakdowns are a problem, which is even more reason they should be converted to all-electric cars. Plenty of go-kart companies make electric cars that work great, go fast, and are quickly recharged (or you can just swap out the battery).
What should be done with Autopia is Disney should partner with Tesla Motors to design an all-electric Autopia car of the future. It could have LED screens on it that show you driving along some major highway, maybe even make it touch screen and the kids get a call from Mickey or Minnie or Donald or other characters that can change randomly to make each time you drive a unique experience (a technology becoming more and more popular in resort attractions). Tesla is most definitely representative of the car of the future and the future driving experience. You don't need to mimic fake car sounds, because the cars of the future will be all electric and completely silent. It would be a huge marketing campaign for Tesla and electric cars in general and a great potential future partnership. Disney could/should also use the large roof surface area on top of Autopia and maybe Innoventions to install a solar PV system they can use to store in larger batteries used to charge the Autopia cars, making them a truly clean energy vehicle. Probably could make a deal with Tesla and team up with Solar City as well to get a good deal and a quick install.
Just imagine the huge national and worldwide press Disney would get if they made this massive partnership with leading clean energy companies and devoted one of their top attractions to be a daily working example and symbol of their devotion to clean energy and the importance of its fast adoption.
They could design the cars to be recharged in only a few minutes, or have easily changed battery packs that cast members can then put to charge and swap with a fully charged one. The Autopia track is only about a half mile, short enough to make cars that could easily drive around a couple dozen times before needing to be charged or have a battery swap.
The new Autopia with electric cars would be sleekly designed, all-electric clean cars, have cool gadgets and touch screens to enhance the experience, create a partnership with a new growing company of the future, and send a positive message to the world and youth of the future about the importance of clean energy transportation. They would be so cool and fun I'm sure most adults would want to drive them too simply because they're cleaner and have cooler gadgets than their real cars do!
Like everything in Tomorrowland, all you need to do is use some imagination and really look to the future and you can come up with amazing new or reinvented attractions that actually exhibit intriguing and exciting future advancements.