I've read numerous notes that deal with idle problems with the 2.1L
engine. My idle problem is interesting but different from many of the
others. When I start the engine on cold days the idle is about 1100 rpm
and is smooth and quiet.  However as the engine warms up, in about five
minutes the idle increases to almost 2000 rpm where it stays, also
smooth and quiet.  Sometimes if  I am at an unusually long stoplight the
idle speed will slowly decrease, ocassionally getting back to the 1000
rpm range.  Should I be concerned about this?  Also, yes I have a
waterleaker.  I find two evenly spaced small puddles about two inches in
diameter when the van is parked overnight.  This does not happen when
the engine has been run for a while, I suppose the heat evaporates the
liquid before it can fall.  Again, is this something of immediate
concern?