Found the problem. We sprayed carb. cleaner around the upper intake gaskets and the car returned to a normal idle. Needs a new upper intake gasket. I will follow the intake rebuild in the 'How To' section, as I was going to do last year.
What a relief. At least I know what's wrong with my beast after all!
Thanks for all replies, I hope this helps anyone else who has the same problem. I will keep you posted on when the gasket is replaced how things work out.
Darn Cars!!
