OK,

about two weeks ago I fixed a blown out hose and replaced the
coolant...two weeks later, the LED behind the temp gauge starts flashing
about halfway through my trip to/from work (45min - 1hr, I live in
L.A.).  What usually happens is that I spend some time in stop/start
traffic, during which the temp gauge is stable at half scale and the
light stays off.  Once I get going however, the light starts flashing. 
Once I slow down again, the temp gauge starts moving up as well.  I've
put the thing up and verified that my fix is still good, that there's no
water leaking out anywhere.  Whassup?  I thought maybe the connector on
top of the reservoir sensor shook loose, but after last night's
flashing, Ieft it as is for an experiment.  This morning, after flashing
initially at startup, the light went out and stayed out till I got on
the 5.

Any ideas?

Scott

(Thanks all for advice about my steering.)