OK ladies and gents. I just swapped my Y7 intake mani with a Y8. I'm i bought a stock Y8 automatic TB also. I finished up my work earlier started my car, and idle jumped straight to 4K dropped to 1K then to 3K going back and forth. So i unplugged the IACV and it flucuated from 1K to 2K. My question is what would happen if I left it un plugged and just ran my car like that. Would something crappy happen to my ride? I know that coolant flows through it, but does it pump it through or does it just steady flow? I know it's a dumb *** question, but i would greatly appreciate the knowledge. Peace!!!

 

If the IACV is not energized, it will stick closed, all it is is a plunger that opens a certain distance to allow idle air to pass. (in conjunction with the PCV air) If you unplug this and your idle is higher than 450-500rpm, then you have a leak somewhere. Nothing bad will happen to it, it will just idle like crap. Did you perform the 3 wire to 2 wire IACV fix, or is your Y8 manifold from an automatic as well.

 

The intake manifold is from a 5speed. I made a block off plate that fit perfect. I didn't wanna cut my harness.So i did that and bought the auto TB. I still have the old IACV and plan on switching them tomorrow.