This swap was all recently assembled with parts such as IACV/FITV cleaned and new seals/gaskets on everything. When I start the car it idles above 2k RPM, but when it reaches operating temperature the RPMs drop very low and surge back up constantly. Had a spare MAP on hand but that made no difference. If I unplug the TPS it no longer surges but still idles above 2k RPM. I attempted to adjust idle with the screw but the only difference I could make was it going even higher. Using my finger to cover the inner holes in the throttle body did make noticeable impact on the motor so logically that means IACV/FITV are doing something? Cooling system shouldn't have any air in it and the small hoses around the intake manifold did have coolant in them when I checked.

At this point I'm not sure if the high idle and RPM surging are two separate issues or if one is being caused by the other. Any ideas?

 

Well nevermind... I think I've concluded the FITV and IACV are actually both faulty.

EDIT: also the TPS was messed up. When in doubt check everything I guess.