air flow mass meter ?

Hi All
I'm new to the site but been scratching my head over my 55 plate TD4
It has been to several local garages due to very poor running revving up and down and trying to stall after new fuel pump and fuel regulator it was still the same the airflow mass meter was unplugged and said it runs better after loosing faith and money on the local garages i replaced the air flow sensor myself yesterday
the car runs but lacks power at the low end of the rev range through the gears anybody had this before or any idea as to what might be the problem i would be very grateful for any feed back

I would say, use this section for a quick intro about yerself then post problem in the gay I mean freelander section