I have a 2339 cylinder 4 knock code with engine light on and flashing coil light. Car will start fine 10 seconds then starts coughing blue/white smoke diesel smell and will struggle to run unless I drive away and warm it up then runs ok, could it be air/temperature related? have had injectors tested, changed filters, cleaned EGR. I have an F-super 2 diagnostic but it doesn't recognise my ECU, I have tracked the unit and it is a standard Ford unit although seems to be 2002 spec, I have a feeling these late 2004 models were a collection of old bits before they changed engines the following year.Have looked at some of the sensors but nothing obvious. Can't get rid of the coil light no matter what, even using a Snaptool scanner. Any ideas?