1999 318i 8valve rough running
 

can anyone help.
i have changed my air flow meter today because off a fault with the old one.
after putting the new unit in the car it has started to idle rough
and black smoke puffs out off the exhaust.
so far i have changed
coil pack
air filter
h t leads
fuel filter
checked fuel pressure it runs at 2.4 bar at idle and 3.0bar when driving.