If I remember right swapping the purge connector and IAT is the common one to cause issues. Make sure the intake air temp sensor has the correct connector hooked up. It should be a connector with two wires one will be (Green/white) the other wire will be (Red/Yellow). The purge solenoid will have a (Yellow/Black) and (Red).
IAT will be the white sensor that is held into the manifold by two phillips head screws.