Why does my supercharged civic's idle go up and down once I start my engine. It didn't do it when I installed the JRSC, but this past winter it started surging...more when cold. It's none of the common things(vaccum, IACV,etc). I think it's something to do with the cooling system, or 02 sensor, or something else....... I'm not sure help.

are you throwing a check engine light?

a better description of your surging would be nice.

how do you know its not a vac leak? you checked the vacuum with a gauge? if you did then what is the actual readings? how do you know its not the iacv? all vac lines and fuel lines are where they are supposed to be? compression results show?

a better description of your surging would be nice.

how do you know its not a vac leak? you checked the vacuum with a gauge? if you did then what is the actual readings? how do you know its not the iacv? all vac lines and fuel lines are where they are supposed to be? compression results show?


Second that

i thought right away that it was either vaccuum or the IACV (idle air control valve), but i guess not.

did u try cleaning the throttle body out good with carb cleaner

that was for 94civicvtecex

has ne one heard about this sport compact pro sponsorship thing whats the story be hind it?

i had the same problem with my civic it is a simple fix you have to order from the dealer a fast speed idle valve. it is located under the throttle body and is connected to a coolant line.