High pitched squealing noise when i start engine

It sounds like your serpentine belt is going. I would have that checked out for wear and also have the pulleys that coencide with it checked as well.

check vacum pipes

I know i have the same problem, and i also noticed than when i open the Hood the whistle just stops, so i figure out it must be some air cycling in or out osmewhere, I found out my air intake connected to throttle body was misplaced a weird gap was left open allowing air to whistle. u might wanna check there

drive belts.lights increase your alternator's turning resistance a loose belt will slip and squeal

The high pitch squeal ia most likely the serpentine belt on the front of the engine you can buy some belt dressing from the part store and put it on there and fix that or some soap will work also, the belt may also need to be tightened. As for the egg smell if it smells like eggs it's the catylitic converter doing it's job and is normal, although you should not be able to smell it inside the car when driving you may have an exhaust leak and could be very dangerous carbon monoxide exposure.

it could be the engine belt or the brakes are bad listen to where it coming from and you will know which you have to change

It sounds like you could have something seizing up. I would remove one belt at a time till the squealing stops. Then examine pulleys to see if they spin free. If a pulley seizes, it can actually make the truck hard to start, or not even start at all. It will act like you engine is locked up.

Thanks Jay!

Seems like a drive belt problem, to confirm pour some water on belts the noise should go away or may get louder for a second. If either happens the belt or belts needs to be adjusted or replaced. Good Luck, If I fixed ya, leave me a FIX-YA comment thanks

Is it a squealing noise?  If so check the serpentine belt tension.  Please describe the noise as best you can.  Yes have a mechanic look at it, in some cases you can prevent a failure that will strand you.