Squeak near throttle body....???

[p71nmd]

1999 Crown Victoria P71 w/ 4.6

When its cold i start my car after it cranks theres a noise like gears or something catching a slight rumble kinda hard to explain since my cats are bad it kinda sounds like my cats when i rpm around 3000-4000(ya know the heat shield sound but its the cat inside) then if it doesn't make that noise it will make a squeak like maybe a belt or sounds like a loud hamster or mouse squeak lol and when you rev the motor the squeak gets quieter with every rev then the noise is gone!These noises are coming from the back of the motor! Not inside the motor or the near the main belt but like near the starter or behind the throttle body! My catalytic converter is bad can it be making this noise on start up?? But what can squeak like a belt behind the throttle body then just go away once u drive it? PLEASE HELP ME!!!

thank you,
Jay

[drock96marquis]

It is hard to figure out just where a noise is coming from. For good measure, I'd remove the FEAD belt, and start the car for just a minute when cold. Do not drive the car or operate long w/o the belt, as you can overheat (no waterpump circulation)
If the noise is no longer present, replace the belt, idler and tensioner pulleys - these are the most common causes of the noise you describe.

The squeek could be some sort of vacuum leak, or it could be an IAC malfunction (however, this typically makes a loud wooooo sound)