FiTech EFI system

Rule out the usual suspects first:
-Vacuum leaks? I had a lean pop through the throttle body once and it blew the big pcv cap off. Make sure everything is sealed up.
-Exhaust leaks before the O2 sensor?

And don't be afraid to reset everything and start over, focusing on the IACs first and only after the engine is above 170 which is the default break point.