Why don't these sound files work

On the weathered D59 by Billegulla, there are some files in the engine sound called
loco_stationary_fast.wav
loco_stationary_med.wav
loco_stationary_slow.wav
smoke_stack_hiss.wav

I listened to them and none of them make a noise in game. Is there a way to fix this or if it is on a timer, how do I make it so it starts sooner.