Unhappy Engine Noises

Michelle pokes her head out from underneath the train.
I think that’s it.
She puts a large piece of leftover hose aside and crawls out.
That was quick. Nice work.
Jack walks over to the compartment holding the batteries, takes the cables off the terminals, and hooks them up to his makeshift power supply. Then, he starts the generator and climbs into the train. Michelle follows him and they go to the driver's cabin. Jack turns the key switch and parts of the dashboard light up. He flips the switch for the fuel pump.
Well, this is progress already.
He points to the fuel pressure gauge; the needle slowly creeps to the right. He pushes engine start button. The engine begins to turn over but it doesn't start. He holds the button. The engine begins to turn over again. After a moment, it accelerates but it still doesn't run. He keeps holding the button for a while but the engine won't start.