intermitent won't start problem. Might start when I turn key a couple extra times or a 1000 times, til my fingers are sore. Sometimes I have to leave it and come back later, but sometimes I'm a ways from home. Just doesn't make sense.
Need more info, define "won't start"... Does it crank, but not fire? No cranking?
Common generic (I don't know anything specific about Dodge Grand Caravans) causes include: Bad coil, power transistor/ignitor, ignition switch, broken ground...