My engine is running better than ever but I think my lsn is still too rich. When I come to a stop, it will idle up for a few seconds then idle down and hold that idle for as long as I want it to. Another thing is when I let it run the tank empty at idle it will idle up some before it quits. According to the tuning bible my lsn is still a little rich but when I lean the bottom an hour or so it seems to get that tinging sound of a lean bottom. Is the perfect tuning window that small for the lsn ? Im having the hardest time with the lsn, anyone with suggestions ?