Also, nova is a Latin word, so obviously it means nova is Spanish. Saying it gets read as "no va", is like saying English speakers read carpet as "car pet".
Spanish "new" = nuevo, nueva . "nova" is not a Spanish word. You are right that the connotations of any non-word may not be determined by the most obvious decomposition into syllables. But "Honda 0" (car) hits entirely differently from, say, "Coke Zero". (btw, "honda" is Spanish for "deep".)
As I mentioned earlier, it's a Latin word, and Latin was already a dead language when the term was coined, so it doesn't get translated; every language uses the Latin term, or its transliterated equivalent.
Regardless of the etymology, when the car was released, the term "nova" had long been in use, for the astronomical event.
