Just developed a new problem this week. Symptoms are, rough idle, (missing) oil leak, and vacuum hiss. Oil leaks are cauing a lot of white smoke, so they are pretty high on the engine, and running down. I never noticed the vacuum hiss, so I am not sure it is an issue. It is coming from the Boost contol valve. All the sympoms happened at once, so I think they might be related. Car was running fine before this. Any ideas?