Nissan Mistral R20 TD27 1996

I have a problem that has progressively worsened over the last 3 months, after driving for 10klms when approaching traffic lights, intersections or coasting to a stop my engine will appear to starve for fuel and chug to a halt, if I select Neutral and put my foot down it will some times recover as if it is trying to recover from being to rich.
When stopped I can restart it and drive off, If I drive my left foot braking and keep the revs above 1500rpm the problem can be overcome.
I have noticed that on a cold start in the morning the glow plug lights up but it now turns over 6 -7 times before starting but runs as if it has not glowed beforehand.
I have recently blanked the EGR system because I put this down to the EGR servos being clogged and not working correctly, they were only slightly sooty.