Started out on a short drive to pick someone up, noticed that the car (Xantia LX TD 1.9 93 reg) made a sort of whistling noise when idle and when revving roared like some sort of the suped up boy racer machine. Since the noise was coming from the rear and was accompanied by a mild rattling, I assumed exhaust problems. Upon first inspection there appears to be a break (rusted out) at the point where the exhaust pipe enters the much wider part (silencer?) and smoke/gasses don't appear to be entering the wider part and ending exhaust pipe at all, instead they come out at the break.
Ok, so now for the stupid questions. A) Do you think this is definately the problem and could it relate to anything else being faulty (I've not noticed any problems before this and it drove/drives fine). B) Is it safe to drive for a while with it like this and will driving with it like this mess up anything else/fill the car with toxic fumes and kill my rear seat passengers :p? C) How much do you think is reasonable for getting this repaired (price)/is it likely to cause any other charges/problems that could cost a lot. D) In Relation to question "c" has Citroen put anything odd in when it comes to exhausts...
Any help would be much appreciated.