I have a 2012 fiat 500c which has problems the dealerships dont even have the answers to. The car is shaking backfiring puffing black smoke, stalling, and now its not even starting. Ive changed the MAP sensor,coil,sparks plugs. I even sent the car out for diagnostics which he couldnt even give me any answers either . The car did this about 2 months ago and then went away completly by itself, and now it came back, more angry than before :bang:
Is there anyone that can help me????????

Firstly don't change things that may not be broken it can make it worse, have an independent auto electrician look at it, it needs real time engine parameters reading and compared to what it should be not just looking for fault codes, black smoke is over fueling or unburnt fuel by say misfiring I just had a plug lead fail leading to shuddering and poor running but was clearly visible in that you could see the spark jumping across.
First guess would be ignition timing