the idle on my 2000 gsr swap DA is still high.
I checked and fixed intake leaks, and blead the cooling system, and adjusted the throttle body and the car still idels around 2100-2500
When I turn the air Conditioner on my idle drops to about 1100 rpm, I’m not exactly sure what is left to do to make this work.
Remove the throttle cable and start the car and see where the idle is at. Is it the same? What kind of ecu are you running?
Did you make sure the throttle plate is closed completely.
I had this same problem with my car, I had a leaking intake manifold gasket
Make sure you have it bled correctly, I let my car idle for almost 25 mins with the cap off, squeezing all the hoses toward the highest point in the system (Iac, FITV, or TB heating lines), also make sure your heat is turned all the way to HOT(blue/red dial) so that your bleeding the cooling system including the heater core which also has coolant in it.
while its heating up squeeze ever possible hose to make sure there arent bubbles hiding in corners, U bends that connect the block to the head etc etc. you get the point
At this point double check that all of your intake manifold bolts are still tight, with thermal expansion and vibration they might have loosened up a bit letting unmetered air into the intake stream
Now: disconnect your throttle cable from the body and see if your throttle plate is closing all the way, it its not its adjustable with the small set screw under the throttle arm, loosen it till the plate starts to stick then tighten it 1/2 to 3/4 turn.
Make sure your throttle body is tight on the intake.
With the air intake tube(that goes to the throttle body) off,
unplug your IACV and start the engine, it will throw the IAC CODE, ignore it
Watch your idle, when the car is at operating temperature check idle speed.
Now if you can properly set your idle to 850 ± rpm do so, shut off the engine, plug the iac back in (iac is ot as coolant is flowing through it) and reset you ecu by pulling the ECu and Backup fuse for about 5 minutes and reinstall.
IF: you couldnt get the idle correct with the idle screw then your getting unmetered air in from somewhere.
with the intake tube off look at the throttle body, there are two passages right before the throttle plate, the lower is for the Fast idle thermo valve, the upper is for the IAC. with the engine running at operating temp with the iac unplugged,Carefully place your finger over the passages there if any vacuum is drawn by these to ports you know that either the IACV or FITV is leaking and should be adressed. If both check out and the car is still idling high, check for un connected vacum lines on top of and behind the intake manifold.