by the sounds of things youve done it about right. id have taken the solenoid off your original pump and used that so no worries regarding the immobiliser. if that doesnt help you could try your pump just to see if there is an improvement. are you running with the turbo? the td's have a different pump that can sense the turbo boost to add more fuel. ecu, egr etc shouldnt be necessary, its more for emissions n cold start to warm up a cat. the problem is either pump related or your new engine isnt any good at all, pm me if you get stuck.