Ok, so from what I've been reading, this is one of the worst codes to pin point. Here's what's going on....
Fresh motor with 4,500 miles. 2.5L
While driving, runs good, but feels a little sluggish. All the problems are at idle. Sometimes it idles fine, others it is about to stall out. I've check fuel pressure...holds steady at 60psi. Replaced the regulator. Every sensor was replaced with fresh motor install. New PCV. Cleaned MAF. When I hook up my OBDII and view a data list, my STFT is ridiculously high and holds steady at 42.2. Did a smoke test on vacuum lines and it only comes out at the vent cap on the IAC, but I'm assuming that's normal when the motor is cold and the valve isn't open yet.
I am stumped. Motor ran perfect before this code and nothing seems to help.
Any help with this would be great!

-Rob