2012 Prostar blowing white smoke

Hey Heavyd-I recently had the above posted hi temp cooler installed as well as the IH low side cooler. Was told the EGR valve might need replacing as it was sticking before being cleaned up and reinstalled. Ran good for awhile but had some white smoke today and a loss of power. No code yet. Could smoke be caused by EGR valve?

 

Yes, if it is stuck open the engine will lose boost out the exhaust and result in poor combustion and smoke. When this happens the ECM will see the EGR valve is not reaching commanded position and will set a code and turn on the check engine light. If you are not seeing any warning lights, then I suspect your smoke issue is from a degraded DOC and improper oxidation during a regen which also causes lack of power due to DPF plugging. EGR coolers leaking coolant into the exhaust quickly degrade the DOC and plug up DPFs to the point they are not reusable.