Check the EGR pipework (The concertina metal bit on the rh side of the engine in between the battery box and the cam cover) This can fracture easily (Especially on auto's that have had an EGR bypass fitted)
Also whip off the engine cover and see if the top of the injectors are wet, if so you have diesel bypassing the copper washer at the base of an injector(s)
Have a look quickly, and get it sorted, this is not good for your health!!
