So what I think you're doing is that you're hiding the dash particle node when you dont need it, and you show it when necessary. (i assume you're also setting the "emmiting" property to true only when necessary.)
The reason why the trail particles are going in random places, is because they are staying where you put them when they're first created. So everytime you show the particles node, instead of it showing where you were a second ago, it shows you where you were the last time you "dashed"
A better solution would be to set the "one shot" property of the particles node and to only set the "emitting" property to true when you press the dash button. this way you dont have to hide the node, neither do you need to set emitting to false, as it automatically stops emitting as soon as all the particles go away.
hope this fixes your problem!