2001 pt cruiser, right rear, sounds like a chirping noise

Check the timming belt. and give us more clues When did it stop running, while going 65 mph or what,

Is the sound from one side/corner of the car, does the car pull to one side when you brake?,does the steering wheel shake while braking?...would narrow things down a bit,maybe a CV shaft is worn out?

9 times outta 10 when moisture is involved it's the serpentine belt. Try belt dressing or just a new belt.

In the trunk or rear space there are plastic panels that cover the rear wheel mounts (solid steel bolts under the panels) I installed a Kicker Comp amp and sub in my wife's Pt cruiser and that was perfect. No engine noise or reverse accelorator sound at all. Has been in for 5yrs now without a need to touch anything.

Probably engine coolant, check its level. If you are brave enough - check the taste of the fluid.. coolant has sweet taste.

wheres it poping from motor or what lol

It's possible that the you have "cupped" tread on a tire or two. After rotation you may hear it. Look at the outer edges of all of the tires for an uneven tread wear. Sometimes it takes a little driving to **** this down. If no luck here, I would stop back at the garage to have them verify there isn't a safety issue.

sound to me that you are having a short in the dash with the radio and sun roof . check the relay see if it gets hot when you open the roof. trase the lines and make sure the two are not wired together.

Check the rear shock mounting bolts... especially the top one.

This is either caused by a wore out strut/shock in the rear of the car or a broken spring.