EGR Delete Info -- Educate yourself

[Waterloo]

One thing to inspect is the SCR system. Look for cracks, crystallization and check the sensors, pull and inspect. That is where I would start, as that can be one really buggy system and will not always throw a code. Also, go through the engine sensors, I would pull them all and replace with new ones. Also take a look at the doser, make sure it is clean and not all carbon'd up. If the doser is gummed up, replace it, there is a core deposit on it, so don't pitch it.