For the days and nights since my last post, my lovely 850 has started every time I've tried, and it has taken me to and from every destination. At first it seemed very tired and reluctant. The gas pedal didn't do very much at low rpm's. Now she wants to "go" a little more than before, but still the same problem. I'm less convinced its the 02 sensors, maybe the timing, fuel pressure regulator or even knock sensor. We'll see. So little $$, so much to repair.