Ok, my joy was a bit premature with my car, it's problem has evolved. Since fixing the o2 senser connection the car runs better. But now when it has decided to stall at junctions when hot.
After a bit of playing around, the problem only occurs of you go from above
2k(ish) rpm to no throttle and no clutch then it hunts badly and stalls. If the car decelerates down to about 1000rpm before putting the clutch in then it's fine. Revving it to above 3k for a few seconds also brings it on. I think it's overfueling and briefly flooding when idle.
Checked the throttle position sensor with a meter and it's ok. MAF sensor was unplugged and the car felt weak when driving.
(Previously changed plugs, leads, coil pack, crank sensor.)
David