Rep Power: 0

Hi all,

First post here, although I have been here several times to read up on different issues with my civic.

Setup: 1997 Honda Civic, Automatic, 1.6L MFI VTEC SOHC 4cyl, with no CEL.

The issue that I have is idle hunting. When I start the car cold it idles rather high for a minute and then begins to drop down to about 1200, and then shoot right back up again to about 2500, repeating this loop indefinitely. It will not idle normal unless I put it in gear. Then it settles down to normal.

I've read all about the cleaning of the IACV, throttle body and vacuum leaks. I've cleaned what I think is the IACV but it still does the same thing.

I've been told by some other folks that it appears that I have two IACV's on this engine, and that the TB on it is not original. That may be the case but it's the way it was when I bought it back in 2007. It has been running fine up until a few months ago when this idle hunting issue began.

I don't know much about these engines so please be patient with me as I learn it. I will post some pics of my engine below and try to explain what I have.

Below is a pic of the TB with what appears to be an IACV on the bottom.



However, when I watched a youtube video about the cleaning of the IACV they showed the IACV on the aft side of the engine with a black plastic body. It appears that I have that IACV as well, as you can see in the pic below. The only difference with my setup is there is no wiring connected to the black plastic valve. The coolant lines are however, connected.



This is all really confusing to me and I'm not sure what to think or do with it. Hopefully someone will be able to make some sense of it all.

I'm sure there will be many questions asked about needing more details, so I will do my best to answer them.

FYI: This is an automatic transmission and there is no check engine light on. I have not looked for codes in the ECU yet. I'm waiting for my code reader to be delivered today.

Thanks for any help.

RC

 
Rep Power: 0

Never mind, problem resolved. IACV on the TB was stuck open. Cleaned thoroughly and now it's working properly.