I am trying to troubleshoot a misfire during cold startup, ( the LTFT jumps to 15, and the vacuum is like 12, until about 30 seconds after start and them it magically drops). The misfire trips the CEL with a Misfire on Cyl #2 code, or general misfire.  I posted on here for some help, and Enki is helping out (seems to really know the platform).  My LTFT is also high at idle, so I was looking for sources of air leaks, hence the smoke test.  The EGR leak was the only one I could find.  I saw on another source on the web (forget where) the a leak at that location of the EGR was normal.  Seems odd I must say.  I guess I could open it up and have a look, may it's gummed up and not sealing?  I suppose I could jam some plumbers putty in the opening during start-up and see if that helps.  Couldn't you see the BOV O-ring leaking on the smoke test?