Mercedes Benz C Class Intercooler Problems

Hi need help with the above, have change already 2 mechanics costing me heaps this stupid problem the light keep coming on after going for a new sensor, then a Air Flow Meter has been replace it cost me this part $644.00 $ 50 1/2 hour jo...

i have recently noticed that my car is emitting black smoke when i pull away from traffic lights or put my foot down it isn't a lot but i would like to remedy the cause

Oil leak was first the sump gasket and intercooler pipe, now a cracked sump!