Cold weather squeal

Just for testing, a few seconds, will the vehicle start and run w/o the belt? Have a helper work the throttle, is the sound gone? If problem not the belt, check the belt driven accessory. Sometimes you can use a long metal rod of some kind, with belt on, one end of the rod touches accessory housing, the other end goes on that bone behind your ear, helps to magnify the sound. I guess you could use a mechanics stethoscope to do the same thing. Have helper work the throttle while you listen to each. Don't get tool or anything caught in belt. This is a serpentine belt, I haven't looked?
Maybe an accessory trying to freeze up or bad bearing? I can't think of anything else at the moment?

To address your first problem squeaking brakes aka "brake squeal", is most often casued by one or 2 things: "Pad vibration" or a "low brake warning sensor".

Pad vibation is usually caused by ineffective pad anti-rattling clips & hardware that allow the pads to vibrate at a super fast speed whenever the brakes are applied, thus causing a high pitch brake squeal. To correct this, replace all the pad hardware and anti-rattling clips and make sure you use a quality pad set that has anti-rattling plates attached to the backs of them. Weather conditions do affect brake squeal, that is why it seems to be worse at times.

Low brake warning sensor squeal occurs when your brake pads reach the point of replacement, the sensor attached to the pads scrapes on the rotor which produces a high pitch squealing sound to warn you it's time for new pads.

As far as your second problem goes (a knocking sound), I'll need more information about the problem before I can offer a possible cause (eg. happens on left or right turns, while going over bumps, at high or low speeds, accellerating...).

You state you changed plugs and wires - Do distributor cap & rotor? If not you should then set timing. That should cure hesitation (might change fuel filter also and run good fuel system cleaner through it)
Prob 2 - sounds like a u-joint or possible brake pad/rotor issue. Does the squeal only happen in mornings when cold? Sometimes after sitting overnight, rotors get condensation and when backing out they'll squeal/grind. Somethings to look at...

You need new brake pads . it has a metal tip that squeals on the rotor when they are worn.

The probable causes are: 1. The drive belts are slipping. 2. The drive pulleys for some engine accessories are misaligned. 3. You have turned the steering wheel to the limits. 4. The drive belts are loose.5. Your brake drum backing plates are rubbing against the brake drum. The brakes also might be a problem. check the brake drums/discs. Finally check your wheel and wheel alignment.

Be gentle with my rating. I am a long ways away. It sounds like a fan belt. You should pop the hood next time and see how it sounds when you have the squeeling going on. Fan belts will squeel until the get warmed up and then stop because the heat makes them grab the way they are ment too. Let me know, Raz

it sounds to me like you need to replace your hub assy bearings

It could be a pulley. Best way to tell is to remove the belt and turn each pulley one at a time and see if you can either feel one not turning freely or try and duplicate the squeal. Keep in mind there is no load on the pulley without the belt on it so it might not be as pronouce as it would be with the belt on.

Replace the motor. Lee

its your secondary air pump. it turns on in the cold morning to inject more air into your exhaust, something about emission. its normal to be high pitched. once on my car it was way loud, i looked and the hose had disconnected. either way its normal if its not super loud. but if its everyone is looking at me loud then check for loose hoses!