... We then did some research and found this Decel RPM Decay setting. This setting controls how quickly your engine returns to idle. I lowered the value and boom!!!! fixed. ...
First of all sorry to hear about the fire / smokeout. Hope it's not too bad to get back to normal.
One question, why did that value get so high? I'm glad you were able to find it but just wondering how it got there. Good to know it was nothing hardware-wise and just a setting. Thanks for the tip on the vacuum caps too.