Dat_boi

I used the search function for hours but nobody else seems to have a problem quite like this. Thanks in advance for any help!

So I'm driving a manual 95 gsr with a 93 b18a1 engine and tanny swapped into it (other engine blew). The egr has been deleted and it has the ls ecu with the gsr wiring harness. My only mods are a 3 inch sri and headers to the gsr exhaust. My problem is that the idle surges when cold from 2k to 3k but after about 5 minutes the problem goes away and it idles at 800. So obviously at first I thought it was the FITV since it seems to be related to heat, but when I plug the bottom port of the tb the problem doesnt go away and actually all of the suction is coming from the top port which goes to the iacv. Another weird thing is that the idle problem goes away if i open tb plate at all. So I guess my only options are iacv and tps but I've never heard of either of these systems having a heat related problem like this.
I've tried blocking off the fitv, cleaning the fitv and iacv, and screwing in the fitv valve (though it wont screw in until tight so it could be stripped). I've bled the coolant too and replaced the pcv. There are no CEL codes