Elevated Idle Issue DCSB 4.0

I have a 2007 DCSB 4.0 6spd and recently my idle while in motion has been higher than normal. Typically idle will stay around 1100 when in motion with the clutch in or in neutral and once almost stopped it drops to 700ish rpm's. Recently when slowing down and pressing the clutch in the rpm's will drop to 1100 then slowly work its way up to 1500 until the truck is just about stopped then it will drop to 700. If im in 4th gear going almost 30 in the 1500 range the truck will actually drive itself as if cruise control is engaged when i take my foot off the gas. One key thing i have noticed is they truck wont do this until the truck is warmed up after about 5 minutes of driving. Could a bad coolant temp sensor cause this?

Troubleshooting so far.
Cleaned MAF
Replaced PCV - PCV ended up being good but i replaced it anyways
Cleaned Throttle Body
I've looked over vacuum hoses but didnt see any cracked lines.

I'm no expert but it is my understanding that the throttle body controls idle since we don't have an ICV.