I don't know about the 07 2.3's, but the OLDER versions of the 2.3 had a PS pressure switch installed.
That PS pressure switch will sense low PS pressure at idle, signaling the PCM to boost up the idle (by electrically actuating the IAC).
Your problem could be as simple as a bad PS pressure switch. When sitting still at idle, turn the steering wheel and listen for the idle to increase. If that doesn't happen, you either have a bad PS switch or a bad IAC.
I would look into that and strongly recommend you flush out the old PS fluid (ATF) and replace it with synthetic ATF. I've also heard good things about a Lucas PS additive/fluid, but since I had success with synthetic ATF, I never tried the Lucas stuff.
2000 2.5 MO5D 4.10 one-wheel drive DD - gave to my older son
1990 STX 87 2.9 going in.....Junked it
2000 3.0 4WD M05D 4.10 S-cab Off-Road package with 235-75-15" tires, hotrod DD, lol