What is the cabby saying (and in what language) in the movie Quick Change?
It sounds like he is a non-English speaking person imitating a New York cabbie saying, "Where the hell to?" Only he doesn't understand the answer because he doesn't speak English. He also doesn't understand traffic laws.
It has been suggested that he was speaking Arabic since he is of Lebanese descent, but this interview dispels that notion since he does not speak Arabic. Wikipedia refers to his character as "linguistically unidentifiable." And this review from the Washington Post describes the character as
Blaftoni (or bluftoni as it is more commonly spelled) appears to have been his word for "bus" - though it is not the word for bus in any real language.
In recent years, Shalhoub has taken up the cause of biases against Arab-Americans with film projects like "T for Terrorist" and "American East."