i have a ls vtec with a gsr head and have been trying to figure out why my idle is hunting. I plugged all the vaccum lines and i remember someone saying its prob the IACV.. just wondering if there is a deff way to know this is bad, or where i can get it.

 

check vacuum hoses for leaks/is your O2 sensor in the header/maybe bad TB gasket

 

i plugged all vaccum, i bought the head and have never taken the tb off.. and no i have blocked o2 sensor which is how i run all my cars, and never had a prob besides running rich

 

https://honda-tech.com/forums/honda-prelude-4/end-all-idle-surge-bounce-etc-problems-thread-1979500/