Have everything in, exhaust on and running
Idle was running high, 1500-1800RPM, pulled the IAC to clean it and was in pretty bad shape so bought a new one. After installing the idle dropped to @850 but after a few seconds of running I get this funky thumping sound coming through the intake, sounds like something cycling back and forth and when I goose the throttle it stumbles for a second before picking up which it didn't do before. Seems like I swapped one problem for another, any ideas?
Read online that Fords had a similar issue and it was related to the throttle position sensor, currently that's probably my next step is to replace that.
Edit: Swapped the TPS, no go, same problem. Unplugged the IAC while truck was running and problem stopped, went back to my original issue of high idle, so either I got a bad IAC (Old one was frozen solid) or something else is going on. Took the IAC back to the parts store and will get a new one tomorrow to try. Did do the FSM procedure for the IAC and it appeared to not be working. Unplug Engine Temp sensor, with IAC plugged in turn ignition to on and it should open halfway, the one I had never moved from where it was with the power off. Could move the valve by hand easily and could feel the vibration of the solenoid/magnet going.
Here's a link to a YouTube Video I posted showing the problem
https://youtu.be/hy3vRcXF6TE
