What happens if you get bad gas? How does it make it run?

A 400e should be ran on bare minimum 93 octane from a top tier fuel station first of all. For example: Shell, Exxon, BP, etc. If you are purchasing fuel anywhere else this can be your first issue. Non-Ethanol would be my preference especially on a rare car like you own. Bad gas or gas that is contaminated with water from too much ethanol concentration or just bad luck can make a vehicle run rough, skip when accelerate, and eventually shut off completely. It can also damage the engine if you do in fact have bad fuel. Of course there are many factors that can contribute to poor runability. I recommend contacting our service department to schedule an appointment and have the vehicle diagnosed before you spend any unnecessary money. They can be reached at 336-993-5506 or info@carminesimport.com. Your can also visit www.carminesimport.com for more information or to schedule an appointment.