Thank you everyone for all the responses to the OXY sensor and water
leaking problems of my friends '84 5000S. Alas, another problem has
just arisen. The car's climate control unit has decided to stop
working. All the buttons on the panel are switching, but the fan does
not blow. BUT, it is not the fan motor, because it does run when
hotwired to the battery. After tracing the wires around, my friend
suspects the AC-Delco board just under the plastic shroud in the hood.
It's the circuit board with a couple of heat sinks on it. He has had
grounding problems with this board. Does this sound familiar to
anyone? Any ideas what the problem might be and/or how it can be solved?