I have a 2004 350Z with over 188k miles on it (original owner). I was told a year ago that I had an oil leak, but that it would cost a lot of money to fix, due to having to take apart the engine and hours of labor; therefore, I was told just to keep an eye on it. Now, I'm told that the leak is because I need new valve cover gaskets. How am I to know whether it's just the gaskets that need replacing and not something more involved? I don't want to repair the gaskets only for the leak to continue. Thanks.

 

Read [this thread].

I stand by the dye kit diagnosis.