Hi, Great West,
I would try and check out the error log and just see if any faults are logged this May give a clearer indication as to what is wrong. It would appear that you do not have and idle screw on your regulator as every thing is governed by signals from sensors sent to the ECU which In turn will regulate the fuel system. maybe a sensor has failed or is failing. It sounds like the engine is running a bit rich, maybe the engine temperature sensor is failing and is a common failing but there a few other possibilities, and it's no good getting into a situation of changing sensors and injectors to try and eliminate the problem.

Regards Nero