Idle issue.

I know almost everyone's had it, or heard it. The infamous rev, up rev, down, repeat idle. It goes up about a grand, then drops back to where it's supposed to be, then revs right back up, then it keeps doing it over and over. Is there one thing that 'causes this? Obviosly my car is doing it.

What's weird is if I turn my vent on, it drops the idle a bit and stops. :uhoh:

bump....
i got the same issue, ive been told replace the o2 sensor but i dont got $65 to waste on a 'maybe'. anyone got any suggestions/similar experiences??

check for vacuum leaks. take off iacv and spray it down with carb cleaner. if you have a fitv thats that off and screw it back in all the way.

thats about it

replaced o2 sensor... didnt go oem, got a cheap one for $35. idles amazing. exhaust doesnt smell rich either.

there is a test that you can do to see if an o2 sensor is bad. Not sure myself how to do it but i have seen write ups on it. do some searching on o2 sensor test or something. I think that binghamtonlife web page had some info, but last time i tried to pull it up it wouldn't come up but that was a while ago so it may be up again.

take off iacv and spray it down with carb cleaner.

had your same problem and did this ^..my idle is PERFECT now, and there was so much crud in the IACV that it's no wonder, no idle up and down anymore, it takes about 30 miles for your ECU to get used to it and it's smooth idle from there (at least for me :) ). Thanks civickiller.

hmmm so the idle was fine for 2 days then it started surging again... i would liket to check if my IACV is dirty, but i cant find it... i got a 88 civic dx. anyone got a pic or a decent description of where it's at. seen other posts with links to pics of manuals but they all dead links now... thanks

ok so i think i found the iacv... (to the right of intake manifold, 2 coolant hoses.. looks sorta cylindrical with a metal piece screwed into its left side, and a black round plastic piece on the end, where a green plug plugs in). when my car starts to idle erraticly, i can unplug it and it calms down... when i take the iacv off, i see 2 side by side holes, neither have screens (on the iacv it self, or on the engine). Where should the screens be that get clogged with carbon? when i look into the iacv the hole closest to the black plastic piece has what looks like a metal shaft with threads on it, and the other hole looks like it has a spring in it (alligned horizontaly) am i looking at the right piece? it doesnt have any carbon on it... any suggestions? this idle thing pisses me off

ps, is it iacv or eacv?

ok so i think i found the iacv... (to the right of intake manifold, 2 coolant hoses.. looks sorta cylindrical with a metal piece screwed into its left side, and a black round plastic piece on the end, where a green plug plugs in). when my car starts to idle erraticly, i can unplug it and it calms down... when i take the iacv off, i see 2 side by side holes, neither have screens (on the iacv it self, or on the engine). Where should the screens be that get clogged with carbon? when i look into the iacv the hole closest to the black plastic piece has what looks like a metal shaft with threads on it, and the other hole looks like it has a spring in it (alligned horizontaly) am i looking at the right piece? it doesnt have any carbon on it... any suggestions? this idle thing pisses me off

ps, is it iacv or eacv?

that's the part. Mine had a screen on one of the two ports that go into the manfold. What I did was just get carb cleaner and fill it with it, spraying everywhere and shaking it with it in it and everything, got it nice and shiny. I'm pretty sure it's IACV.

if you unplug it and your idle stablizes then its your iacv. so either clean it and try to see if it works or get another iacv.

ok... so i did what u suggested civickiller... took off icav, sprayed it down... put it back on. (took connection off battery to reset ecu). first time i fired it up, it started to idle high again... (i didnt touch the gas). turned it off... then went for a short drive around town. the idle hasnt gone up since. more testing is needed, but maybe we did it... thanks

ok so i cleaned my IACV very well (let it sit with carb cleaner in it for a good hour... sprayed in it in every direction i could... only clear carb cleaner comes out...) still idles funny. my car idle will only alter when the car is warm... ive read it could be the FIV... anyone had similar situation? i have a d15b2 in my 88 dx hatch. anyone have exp. taking off the FIV? wana help me out? ty.

PS. My IACV doesnt have any screens on it, and to get a replacement IACV im lookin at $75. (id like to be absolutly sure that it is the problem...) :(

Dan

Since you know that we all get it, did you do a search!?