Hi everyone,

I am new to this forum, but since I noticed many of you know a lot about civics and all I am having a huge problem with mine. Recently my civics idle started going crazy. This is after I have been driving 20-30 mins when the car is fully warmed up. I brought it to the mechanic and they said it was the "o2 sensor" because that's why I had a check engine and all. So I fixed that and the check engine left but the car still has the problem. I told him there is a big possibility it is the IACV (Idle Air Control Valve), but he was disagreeing (don't even think he knew what I was talking about) below is a list of the symptoms:

-Car does not have an idle problem when being warmed and when it is cold. Idle stays regular

-after driven for around 15-25 minutes it's starts messing up

-idle starts jumping everywhere from 1rpm to 4 to 3 even to 0 to where the car shuts off

-problem consists once it's started until the car is left off for a while

What procedure should I take so I will not waste a lot of money? I feel that is the IACV after reading so much. But you guys let me know. Thanks!

 

First look for vacuum leaks. They sound like hissing air. Then I would pull off the throttle body, take off the fitv, open it up and unscrew the white plastic thing. Clean it all up with brake clean and let it dry. Take off the iacv and clean that with break clean also. After everything is dry put it all back together and screw the white plastic part of the fitv almost down to the bottom. Bleed the air out of the coolant system.

 

Sorry for the screenshot but that's the only pic of the procedure I have. Look at Ronj@HT's Sig if you see his posts. He has links to guides with pics if you need em.

 

Thanks for the tips. I will send this over to my uncle in New York. Had to leave my car there because I couldn't drive it back to Mass. Hopefully I can get it this weekend. Thanks again. If anyone else has tips feel free to tell me.

 

Tried to post yesterday but browser messed up and lost the post.

Was just going to say that usually idle issues with older hondas is either IACV, FITV or Vacuum Leaks.

I'm not the most knowledgeable on this being most of my research has been on no start diagnostics more than idling issues, but everything I've seen here has always pointed at those three things for idle problems.