With the IACV unplugged (closed), should there be vacuum on the port inside the throttle body?

 

Anybody?? I get vacuum at the port for the IACV when it is unplugged, when I'm trying to set the idle. Idle won't go to 450, even with the idle screw all the way closed. It will only go to 450 if I plug the port for the IACV with my finger.

 

http://www.team-integra.net/fo...52266

 

I think mine is bad, just want to make sure. I have cleaned it several times, like in that post. The valve is not sealing properly and letting air by, either the sealing surface being dirty, missing a o-ring or something else.

 

2 or 3 wire IACV?

Apply 12V battery to terminals, if it actuates - it's not bad.

 

2-wire. It actuates when I apply 12V.

 

Then the IACV is working just fine. That's all it does is accept a PWM 12V signal to regulate open/close.

Unless the actual IACV ring/gasket is bad, I'd continue checking other things.

 

I think that the seal/gasket is bad in the IACV and letting air by when it is closed (unplugged). I am trying to find out if when it is closed is there supposed to be vacuum on the port.

 

Try blowing through the IACV with it disconnected. This will verify if it is default open or default closed. I wouldn't be surprised if it's default open - as a failure case still allows the car to idle.

 

When I had it off of the manifold and it was disconnected it is closed (0V) and open when I applied 12V.

 

So is there suppose to be vacumn when the iacv is unplugged?