I believe you should be able to reach the next battle on the road when you start act 4. If you try it and run out of fuel before you reach it, that sounds like a bug—please email me your save file to christine@loveconquersallgames.com and I'll take a look!
Hey, thanks for the quick turnaround. I tried just that three times (the first, natural realization that I had no money and not enough gas, and then two more times to try what you just suggested) and in each circumstance the car would sputter to a stop and shift to the gas app right after going from 1 turn left to "NEXT" on the closest location.
I'm very happy to email my save, but a quick look around my steam folders has not turned up anything obvious.
On Windows, saves are located in %userprofile%\AppData\LocalLow\Love Conquers All Games\Get in the Car Loser\saves
On MacOS, saves are located in either ~/Library/Application Support/Love Conquers All Games/Get in the Car Loser/saves or ~/Library/Application Support/com.loveconquersallgames.gitcl/saves depending on your configuration.