I have a 99 prelude base, nothing serious, just exhuast, headers, and recently installed a cai, The car now idles from 1 to 2.5k back and forth repeditly.....i thought maybe i pulled a vacuum hose loose installing the intake, well i checked and there where no loose hoses or leaks, then my check engine light came on, so i took it to Auto Zone and they diagnosed it as "Idle air control valve". Which they didnt show me where it was, but i think i know where it is....on the front of the intake manifold im thinking...correct me if im wrong. Well instead of ordering it i tryed to clean it out, so i did and now it still does the same thing. Someone told me my vtec could of came unhooked, where is that at? well, right now im stuck at a dead end on fixing it, please help. Thanks.

 

check the fitv its ayttached under the throttle body its got 2 coolant lines running to it, pull the throttle body off the fitv has 3 10mm bolts pull it off clean it with carb cleaner put it back on if it still surges replace it, every one thinks its the iacv but 99% of the time especialy acc/ludes its the fitv.