blinking water temp light

[bwb24 at drexel.edu (Brad Boston)]

I have a problem where sometimes about 2 seconds after I start my '88
16v rocco the water temp light on the dash will blink at me.  It wont go
out if I just shut it down but if I wait for it to get up to temp, shut
it off and restart it, no blinking no over heating.  If I don't shut it
down and restart it after it gets up to operation temp the heat will
just keep right on going up.  I replaced the radiator fan sensor with a
lower temp one during the summer.  Any ideas where this electrical
gremlin might be hiding?

Brad