okay so my car started to idle up and down. when i start my car, its okay and when im driving it is perfectly fine. When i pull up to a red light or stop sign and put it in neutral, it starts to idle up and down. it bounces from 1000 rpms to 2000 rpms and continues to do so. some times if i let go of the clutch a little and hold it there, itll stop but maybe its just coincidental. i took off my IACV and cleaned it up real good and put it back and it still had a bouncy idle at stops. i even bought some seafoam to rid some carbon but it stopped for a day then it started up again. what could this be? i appreciate any help!

 

The same symptoms came up with my moms car a year ago, sounds like a vacuum hose leak. Get some carb cleaner and spray your vacuum hoses while the engine is idling and listen to see if the rpms level out. If that doesn't work check your gaskets for leaks, but I would expect some oil to be leaking if that was the case. Please post your findings.

 

Click the FITV link in my signature.

Any CEL codes?

 

Ugh, should have thought of that. Still learning as I go.

 

I just noticed you have D16Y5 swap, which doesn't have an FITV unless you have a D16Z6 throttle body.

 

check the iacv clean it and put it back on

 

smh....


What throttle body do you have? Check to see if the cruise control vacuum port behind the manifold on runner 1 is plugged. Mine wasnt plugged for like a year and it had a funny idle.
After that check for vacuum leaks and do screw in the FITV like RonJ recommended.


Do you have any friends whom you can swap the IACV with? If its bad, even if you clean it that wont fix it. I cleaned mine like 3 times and the problem didnt go away till I replaced it.