Peugeot Boxer 2.5 DJ5 no acceleration ???

[shaggy]

Hi every one, I have a peugeot boxer 2.5 non tubo diesel van. The engine will tick over very low idle but will not accelerate unless a small squirt of EZ start used to boost reves, then it will pick up and accelerate fine as though there is nothing a miss. If the revs go below about 1300rpm it will die again and just tick over. I have owned many different Citroens and diesel vehicles (these engines are very similar), always diy but have never came accross such a bazzar fault.
I have checked fuel line (no blocks or leaks), I have replaced fuel filter and sensor gizmo on bottom of filter bowl (what does that actually do?), all filter seals replaced, connections on injector pump look ok (but don't know what they do, it is a Bosh pump).
Don't know what else to do, think it could be somthing simple but have no more ideas.
PLEASE, can anyone help.
PS. Have ran this up with just a fuel pipe into a can of juice from the injector pump to bypass the tank & fuel line. Still no acceleration?

[the moose]

Have you checked the throttle body at all?