[charliebucket]

after some investigative work, i removed the throttle body with iac still attached. i shined a flashlight at front and back of throttle plate at the holes for the iac and saw that they were a half of a hole off. did a port match by grinding the throttle body holes to match the ford iac and ta -daaa, no more whistle. i even checked my last intake set up which also whistled ( cobra intake, with holley throttle body, ford iac ) and saw that those holes werent lined up perfectly either. must be that there isnt much precision work to stamping these out. should have probably gone with an accufab. hope this helps at least one person out there.

[1slo5.0]

Cool, glad you figured it out. I learned something new as well.

[Nice 5.0]

Ill have to look at mine. I thought the whistle couldn't be fixed either. I thought I had a vacuum leak also when i first put on my throttle body.

[Chris951]

I don't have a whistle with my bbk?

[charliebucket]

yeah, i guess its kind of a crap-shoot for how good of a matched part youre gonna get when everything on all of our cars is aftermarket.