loud squeaking noise until engine warms up

I just bought my mustang and it makes a loud squeaking noise until the engine warms up, whether driving or idling. I don't know anything about cars at all... but from reading other questions, could it be a loose belt?

more than likely, get a bar of soap somthing like irish spring, and rub it on the belts, (engine NOT running), if it stops squealing or isnt as bad yes its a belt (easiest way to figure it out short of tightening everything)

more than likely, get a bar of soap somthing like irish spring, and rub it on the belts, (engine NOT running), if it stops squealing or isnt as bad yes its a belt (easiest way to figure it out short of tightening everything)
Well, there's only one belt and usually the serpentine belt will not squeak.

Noises such as you describe are extremely hard to resolve over the Internet. Try and get a more detailed explanation of where the noise is coming from. Open the hood, listen, touch things, you can even use a few feet of rubber hose as a stethoscope to help pin point the source.

i've seen serpentine belts squeal several times, especially if they are old, not saying this is the problem, hence the very easy way to tell, rub some soap on it, and he didnt even say what year it is so it may not be a serpentine, the first thing i would check, yes, would be the belt(s)

1) The next time it squeaks, shut it off immediately and pull the belt off. Start it briefly and see if the squeak is gone.
2) If it's gone, while the belt is off, check all the accessories for loose or damaged bearings. The idler in particular. They shouldn't wobble front to back. If you find nothing, try a belt.
3) If the squeak didn't go away with the belt off, you've got engine problems.

I'm assuming you've checked for belt tension by now.

ok, i know you've heard a lot of things here, tell me, whats easier, soap, or taking the belt clear off? I am a ford MLR and ASE certified mechanic, let me know what happens with the soap thing and i'll try to help you out k.