Nissan Repair: 300ZX hissing issues, vacuum leak, electrical inspection

Question
My 1988 300ZX vibrates when its on and I hear it hissing in the back of my vehicle, probably through the exhaust system, when I turn it off. The hissing sounds like air is escaping from somewhere, but I left it overnight and the next day my car battery was drained and wouldn't turn on. Do you know whats wrong with it?

Answer
Michael,

The hissing noise should not be related to the battery issue.  If it were me I would take the battery down and get it charged.  Second, after the car started I would run it down to Autozone or Checker for a free electrical inspection.  After that, I would daignose what appears to be a vacuum leak.