Serious vibrations.
The idle or pulley will have movement in it, when the engine is shut off. It can also have a visible wobble while the engine is running.
I'm assuming you mean a pulley, which is what the belts run on. If so, depending on which pulley the bearings could be bad or if it is the crankshaft pulley (big pulley near the bottom) the rubber could be getting bad.
The idler pulley has nothing to do with the brakes. If the idler pulley is bad it could throw or break a belt, and then your engine will stop.
Most likeyl cause could be a bad pulley
The idler pulley is a unit connected to the engine via a brace or bracket. This part merely routs the belt in a certain direction and, if bad, will cause a failure of the total serpentine system or cause belt wear as with any bad pulley in the system.
No, the damper is just a shock absorber.
you probably have a bad bearing
remove drive belt and check all pulley wheels for freedom of movement sounds like a pulley wheel is bad, probably the belt tensioner pulley
Engine noise in a 2000 Kia Sportgage could be caused by a bad water pump, pulley bearings or a bad timing belt. A qualified mechanic could best diagnose the issue.
check your engine balancer pulley on the left side of the engine. It is the big main pulley on the very bottom of the serpentine belt. This pulley has a rubber dampener inside of it and when the rubber breaksdown, the pulley becomes loose and makes a banging or clunking sound as the engine is running. Don't know for sure if this is your problem but its worth checking and it is simple to do
Did you look at the alternator bearings?Take the belt off and spin the alteranator to see if the bearings are bad.
If the sound lessens as the engine revs up, it could be the harmonic balancer. The rubber around the pulley could be bad. This is quite easy to see from underneath the car.