One week after purchase the motor has developed a loud sleek. How do we fix it?

Well I think the best thing to do is to replace the windows control module, the one in the drivers door, but before that make sure is getting power and ground if not you found the problem.

Blower motor ? Take the glove box , plus lower panel ! When it happens , investigate the noise . You don't say what make , model , year vehicle . Don't know whats back there .

This is probably tappet noise from the top end of the engine. However you should have it looked at quickly as these engines had a severe problem with oil sludging, even when recommended services were done.
This caused all sorts of problems, so see if you can get it fixed before the engine develops something terminal.
http://www.enginebuildermag.com/Article/66958/sludgy_saab_may_rattle_your_chain.aspx

could be some really loose belts. solenoid makes loud popping sound and starterclicks.

When do you hear the noise? While just driving, while turning? If it while turning it is very possible that the bearing plates, the plates that the struts bolt too and the plates bolt to the car could be going bad. There is a lot of pressure on these plates and will bind if bad and pop very loudly when they move. I suggest checking those out. Good luck and let me know.

Sounds like your blower motor bearing is going bad. Pull glovebox and you can access blower motor. Pull blower motor and check that fan/cage is tight and not clogged with leaves etc... Had an instance when mine made a bunch of noise found parking stub had been sucked into fan,

might have to remove squirrel cage and assem. on new motor

It really depends what the noise sounds like. Is it a grinding sound? - if so, it could the blower bearings are faulty. If it's a whistling sound it could be just tree's leaves stuck in the ventilation pipes (was the car parked under a tree for any length of time during the Autumn or Fall).

So, what is? Have them say that 3 times in writing. I know California has a lemon law. 3,000 miles? Take it back under warranty and tell them you'll have your attorney pick it up when they determine what cause dthe failure.

I had this same problem. Initially the wipers moved from detent a couple inches, then reparked, then started up and stopped on their own...eventually they stayed on all the time and I had to remove the circuit breaker to get them to turn off. I don't know if this is the RIGHT solution, but I took my car to the dealership and they swapped the motor out--problem fixed. I ordered a non-OEM motor, they put in the first one, noticed a loud sound on high, replaced with a second non-OEM motor, got the same loud sound. I took the car, didn't notice anything out of the ordinary (car always had the relatively noticeable sound on high) but shortly after, the problem came back. Returned to the dealership and they put in a GM OEM motor. So far, (one week) the problem has not returned.