Hey guys, i know this is a very common problem with honda motors, ive had a surging idle for some time now.
set up: turbo b18c with a b16 head obd1 tuned on crome at 14psi

Things i've done:
checked for vacuum leaks none i could find,
checked tps voltage, and i've actually gone to a new throttle body and new tps. good to go
cleaned iacv and recently replaced it with a new one. good to go.
no fitv on my car.
as far as i know i've purged all the coollant of air. let sit idle and opened radiator until thermostat opened and swapped coolant twice.

car seems to run awesome otherwise, it will idle fine for about 10 to 15 seconds and then go from 250 to 1500

its driving me crazy, the only thing i feel is that there is still air in the coolant.

How crucial is it to get every little bit of air outta the system to not have a surging idle.
thanks

sorry for the post but i've searched and searched and tried forever to fix it

 

Air in the coolant will not cause a surging idle. I have flushed and refilled my coolant before with air still left in it, and my car would still idle fine as it was warming up, even though the coolant level was rising at the radiator neck due to the air bubbles expanding. But idle-wise, no effects whatsoever.

 

word. thats what i needed to know
thanks

 

check you iacv valve again and are you shure your car doesnt have a fitv valve those go bad and make your idle even worse!!!