Had another look and when the problem is happening O2 sensor is at .39 volts. If you warm car up and switch off and restart fairly soon it does not happen , leave it 10 minutes it will do it, only other clue is the voltage at the map sensor is a bit varying, sometimes at idle it will be 2.2 volts which I know is too high, other times 1.5 volts, would love to blame it on the map sensor but don,t think it could increase injection duration to 20 ms which is what happens for a short time as mentioned above, thanks, Jim.