There are numerous occasions on which I have seen private vehicles driving around with black smoke pouring out from the exhaust. These vehicles need taking off the road and fixed before their MOT is due.
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I have frequently had to get well away from the road as a vehicle pouring out black smoke from its exhaust has passed. I have seen pedestrians at our village pedestrian crossing engulfed in black smoke as it passed.There is a regular occurrence of these vehicles in our area and undoubtedly it is a national problem. I have tried reporting these to the police,DVLA and DVSA but apparently they are only interested in commercial vehicles being reported.