240sxdrifted

okay guys just to start off i searched and ive been put in so many different directions i dont know where to go..Cold start:revs from 800 to 2200 all on its own..once warmed idle calms down around 1000 to 1500 depending on the day..after drive..car makes whistleing noise that is present during boost(10 psi)and sometimes during vaccum side of gauge....noise sounds like coming from thermostat/temp sensor area..

replaced:coolant line from temp sensor area to bottom of throttle body-this made the noise quieter(but still comes back after warm
replaced:fpr w/gauge(reads 37 without vaccum and 41 with)
replaced2 sensor-astmo bov-hks-3 in exhaust no cat-
cleaned:iacv
turbo:t25 with stock boost pressure sylenoid(10psi)

questions:
what would cause the flucuations with the idle?
Where else should i look for this sound...maybe the coolant temp sens right next to where hose hooks up???theres no leaking coolant

thanks for your time guys...