The IAC (Idle Air Control) is located on the back side of the upper intake manifold. See where the throttle cable bracket attaches to the UIM? OK, just behind that is the EGR valve. (Thats the silver thing with the little vacuum hose plugged onto the top of it.) Just in back of that is the electrical connector plugged into the IAC. Just below and in between the EGR and IAC is the IAC bypass hose leading to the accordian hose. This can cause all kinds of idle problems if it leaks anywhere.
