Temp gauges have been acting very strange.  Started off with red light
flashing but temp normal after driving 25 miles in city traffic.  Problem continued
after swapping out the relay switch twice.

One week later on trip to see grandkids, both the flashing light and temp
gauge went berserk (afraid of kids?).  After first 100 miles of 400 mile trip the
red light flashed and the temp gauge went off the charts.  This was not
during the drive up hill from LA to Gorman on Interstate 5 but after coming down
the Grapevine.  Could going down hill cause the expansion tank to be the high
point in the system with an air pocket?

Pulled over and found no leaks.  Expansion tank was full.  It was full when I
rechecked it after removing cap with engine idling.  Engine never ran rough.
Turned engine off and restarted to find temp in the normal range and no
flashing light.  Drove 300 miles to Sacramento with all systems normal.

First 200 miles of return trip without problems.  Gassed up and 10 minutes
later light flashed and temp gauge off the charts.  Turned on the heater and
gauge and light went back to normal.  Turned off heater to find light flashing
and gauge off chart.  Checked expansion tank while idling and it was full.
Engine never ran rough.

Drove home with heater on and no problems except wife's window open the whole
way.

Since then, changed sensor in expansion tank, new expansion tank cap, new
hose to overflow tank and bled the cooling system.

Has any one else had similar problems?  What did you do to fix it?

Thanks,
George
'88 Westy