THINK I'VE FIXED IT!!!!

Running problems and overfueling when warm has now GONE.

tested all the wiring from sensors to ECU etc and all seemed fine replaced a few tatty bits, then found the YELLOW coolant temp connected was missing its metal retaining clip!

So all the time I thought it was plugged in it actually wasn't all the way on so making no connection, made a retaining clip for it and hey presto fault with plugging Black box back in was gone.

Over the moon now!! Still a little struggle to start it when cold but I can live with that at the moment.

THANKS FOR ALL YOU ADVISE

Hope this helps someone else one day.