Mix some Tylose powder into your fondant or if you dont have any, cut out the shape and let it sit a few minutes to firm up a little before putting on the car. What is under the fondant? Buttercream or ganache? I think ganache would be a firmer foundation in a carved cake like this. Hope this helps.
Did you apply your fondant in pieces or cover the whole thing in one piece? I would lightly lay the fondant over the cake and use the pull and smooth method. By this I mean to pull your fondant away from the cake, starting at the top gently push it down work at the same height all the way around the cake then work down a little lower until you have reached the bottom of the cake. It also helps me to put the cake on something like a bucket to raise it to a comfortable work height. hope this makes sense!
Thanks for the feedback. I'll try anything!
I use buttercream for the "dirty icing" and then I generally roll out into one large piece and go from there. I thought maybe I wasn't getting it thin enough (though that can still be a reason).
Still a rookie over here... just made a handful of cakes. I'm more of a piped icing person than fondant. I just think fondant is so beautiful.
Thanks again for your time!