Thanks for the clarification...
To rephrase the statement, you want to use your tunnelling power to get inside a vehicle?
I would allow this as a "Brick Tricks" alternate use for a power. In my current game, I've given powers to the players (ok, not quite yet but we're getting closer!) and I've got a built in skill of "Power" representing their learning how to use their powers. I imagine they will come up with creative ways to use those powers and I will allow them to use them in creative ways provided they make the necessary "Power" skill roll!
Originally, I mean to use this skill to provide the first appearance of their powers. For example, an electrically based character may discover he/she can teleport through electrical outlets "by accident" upon a successful use of the Power skill.
Clear as mud?