Engine Malfunction lightcomes on.

[Robbiejc843]

I have a 2009 (09) 1.8 TDCi C-Max. It has recently developed erratic running at around 2000 - 3000rpm (Very jerky @ 30Mph). When I accelerate I can see a black plume of smoke (Not blue) on changing gear and about 3000rpm the Engine Malfunction light comes on and occasionally the EML. After this the car runs fine, but slightly underpowered.

The fault codes relate to differences in the MAF and MAP pressures and if the EML light comes onI get the turbo underboost code, which I would expect. I have replaced the MAF Sensor but with no difference.

As I was using FORSCAN to get the codes it stated that it could be a dirty blocked MAF, EGR system fault (Black smoke?) or an induction leak from the Turbo to the intake manifold.

How do I check the EGR system or check for induction leaks? Or could it even be the MAP?

The thing that is bugging me is that the car drives fine after the Engine Malfunction light comes on even though a little underpowered, which I would expect with the Malfunction light coming on.

Any help would be greatly appriciated.