td4 missfire

hi, my 2004 td4 has developed a missfire when starting from cold lots of smoke and poor acceleration upto about 2000rpm, recently serviced,new crank breather fitted {bmw one} inlet manifold and egr cleaned have a new maf that i bought from famous four but it make car run worse lots of turbo lag then it just takes off after 2000 rpm,so put the old one back in, have plenty of power when driving and missfire dissapears when engine is hot,also have fitted a new set of glowplugs thinking that was the problem, could this be a symptom of the ecu running in a default mode ? most greatfull for any help

check your inlet turbo rubbers aint got a split [youve got three] if they are ok, try running with the maff dissconected to see if it improves , if yes then its a maff problem

turbo hoses ok, disconected maf made problem worse. wondering if fuel presure sensor faulty, or the wiring connector