Originally Posted by Chris Peralta

To me that sounds like a fairly stable idle so it does not sound like an air leak to me but anything is possible. Are both of your needles still out from flush? Generally if it idles nice after reving the engine up and then drops down to a lower idle the LSN is set too rich which will cause it to load up and die, especially with too cold of a plug. The colder the plug is the more exact you have to be with the tune in general.