I have a Volvo V50 1.6d 80kW 2008
Recently I've started to hear a weird noise that can only be described as air hissing and clicking. The noise can be heard when idling and it gets faster when accelerating. Also, when accelerating, black smoke or soot will always come out of the exhaust and it seems to be more than the usual amount and to the point, I would consider it not being normal. I have someone claim that it is supposed to do with the car's intercooler but I don't know how true is that. Below I have attached a video where the noise is present. Any help is appreciated :)

 

Are you sure that isn't lifter noise? (perfectly normal) if you add a smidge of engine oil while it is running, does the noise reduce? (do not excessively overfill the engine oil)

Black soot out of the exhaust can be because of the DEF being low or something with the exhaust system not functioning properly. ( I know very little about diesels and the Eco-friendliness of them)

 

Super late update: I had to replace the fuel nozzle ring and the noise went away.