just been on one of these with much like the same symptoms,very bad black smoke on initial rev up and lack of power,changed pump,injectors,throttle pedal,air flow meter,egr valve,checked air intakes etc,but had donor veh to rob parts off,it turned out to be the wiring loom for the sensor controlling the egr valve,try removing the vacuum pipe from the egr valve and see if that helps,if so have a look at the wiring connector and wiring etc.good luck
cdc
August 2011
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