(Que Pedo= What The Fart?, actually translates to "What's happening?")
Most idioms can't be easily, or coherently, translated into another language because they're meant to be said in the original language and may not even make sense to people who speak another language.
(Sepa La Bola = The Ball Knows, actually means "I have no idea")
Even people who speak the same language but are from different regions of the world can't understand each others idioms, so it makes sense that a Mexican idiom translated into English would come out sounding all sorts of strange.
(Estoy Encabronada = I have become a goat, actually means "I'm pissed off")