Jumpy Tacoma, P0505 Idle Control System Malfunction

Hi first genners!
One day I pulled into my driveway came to a full stop then slowly accelerated to the backyard to experience something I have never had on my truck. As I was pressing on the pedal the rpm jumped at around ~1400 rpm. It jumped about 300rpm. I was in drive and this behavior is fully reproducible. It also exhibits the same (similar) behavior when in park or neutral but at around ~1800rpm. I also got a P0505 immediately when this happened the first time. I went ahead and cleaned the throttle body, got and replaced the Idle Air Control Valve (after-market) and voila, nothing. Same P0505 same jump at ~1400. Replaced the vacuum hoses, fairly certain I don't have a leak (I would need a second opinion to be sure). Also, the car drops rpm suddenly when reaching the operating temperature but then it dials back to normal and idles at normal rpm. Would the after-market IAC just not be good enough or someone has any idea what could be the problem? P0505 pops back as soon as I clear the code both when cold or warmed up

 

Would love to know what you figured out? I am dealing with the same problem, checked over everything and cleaned iac valve and nothing, only does it when motor is at operating temperature

 

https://www.parksoffroad.com/tacomamods/maintitems/enginecode/cip0505.pdf

This might be helpful