I have an A220 CDI and have experienced similar symptoms to those mentioned above. I took delivery of the car in late June 2013 and first experienced heat build-up in the engine bay, a smell of burning rubber and power sapping whilst driving. Service Care came out and found no fault. Later symptoms including pinging exhaust pipes.
Ever since, the same symptoms have reoccurred almost two-weekly. After two returns to the dealer, they are now telling me what I had hinted at in the past - DPF regeneration. This is the only fault code that has triggered.
However, surely after 3100 miles of varied driving (usual weekly commute, heavy weekends of almost 500 motorway miles, multiple drives of varying lengths in the day etc.) this would not be occurring every two weeks? This is what the dealer is telling me - they are effectively alleging that this is normal!
The symptoms are that bad that I have called for assistance in the past. I have the 7-speed semi-automatic gearbox which becomes extremely hesitant and indecisive, as well as lacking power quite significantly.
Can anyone shed any light on this issue? I am reluctant to accept from the dealer that this is normal.