This is my first post on honda-tech and im extremely new to the honda world but i just bought my first civic 2 days ago, its a '98 with a D16Y7. After warming up it jumps afrom 1000 to 2000 rpms but when i plug the bottom hole (the one closest to the front of the car)with my thumb it idles perfect... I was under the impression that that was the port for the IACV, but im guessing that may actually be the FITV??? Does anybody know if thats correct? If so how do i fix it? Ive already tried cleaning it multiple times with throttle body cleaner and it seemed to stop the surging but the idle was pretty high, between 1200 and 1500 rpms. That only lasted for a few hours then the same surging problems returned... And tips for me anyone? Im pretty confident that this issue is something with an extremely easy fix, just need to be pointed in the right direction... Thanks for reading my post please respond if you have information!!!

 

Your car has no FITV. Bleed all air from the coolant for a start.

 

Are any CEL codes thrown?

 

Yea im gettin a p0505 code

 

Start by trying to adjust the idle speed using the proper procedure -- follow diagram in FAQs sticky.

 

I feel like theres definitely some kind of vacuum leak maybe somewhere internally in the iac possibly??? I have an extra throttle body im gonna put on and see if that solves the issue because theres no surge with the engine that had that throttle body/iacv on it. But any advice on fixing it would still be appreciates.

 

Why not try adjusting the idle speed first? The only way to have an internal leak is from the IACV rubber gasket.

 

I tried to adjust idle speed and it didnt work. I switched throttle bodies and the problem went away? So some is wrong with the throttle body or iac. It must be.

 

I also need help with this issue, I have a completely stock 2000 d16y7 and it doesn't have the fit valve, also no cel, but a couple of questions.... Where is the bleeder valve for the coolant? And it sounds like a vacuum leak coming straight from the iacv but the seal is completely fine, is there anything more I can do like sealant inside or what other options can I check for?

 

As others stated, check for vacuum leaks and possibly replace the IACV.

 

take the iac apart and clean it with a wire wheel. if it gets even a little gritty it will cause all sorts of wierdness.