Hi Debra, sure gets your attention though doesn't it. I've just finished
with the same problem and it's usually a bad ground from the sender unit.
Ken from Vanagain saved my sanity buy giving me the simple solution.
There is a brown ground wire that runs from to top of the engine, past the
distributor and water pump. Disconnect that from the sending unit and
re-connect to a good ground, like the spade screw on the base of the
distributor. Works like a champ and your idiot light and buzzer starts
functioning properly.
Good luck
Bob Allen
86 Syncro