Update 2 ----

I ran the car yesterday , I did 11 short trips between 2 and 15 miles each and the car ran differently all the time, sometimes not going past 2ooo rpm, then zooming off to 4000 rpm no problem, then slowing down to 2500 rpm. It was erratic with no logical reason.

Also twice from the 11 runs it would not start, just the starter spinning but nothing firing (normally it starts first turn of the key). Both times I found pulling of the vacuum pipe from the right hand side of the vacuum reservoir and releasing pressure it started fine.

This is leading me to think the problem lies with the vacuum pipe or reservoir - any opinions?