ducato 11 jtd smoking like a mad rasta

[wpd]

Help required before i buy an rpg and destroy this pigging van.
The symptoms, Loss of power intermitant, excessive smoke, replaced the cat, fuel filter, and egr valve. runs ok ish if you remove wiring to air flow switch. has any body had this problem?

 

[Ffoxy]

Help required before i buy an rpg and destroy this pigging van.
The symptoms, Loss of power intermitant, excessive smoke, replaced the cat, fuel filter, and egr valve. runs ok ish if you remove wiring to air flow switch. has any body had this problem?

Faulty MAF?