Yeah i will clear it all out. Besides the fuel filter needed to be changed anyway.

UPDATE
 

UPDATE


So this morning i drained the fuel tank completely and then refilled it with fresh clean diesel with additives etc.


The car runs well. No knocks or weird sounds. Acceleration is good and there is no smoke from the back either.


The fuel filter was changed too - that was a pain in the arse but it was done.


I will check the car using INPA or DIS software and erase any error codes on there or deal with them etc.


Thanks for your help guys much appreciated!