Car makes chirping noise when idle

Babying the car has nothing to do with the serpintine belt tensioner…they are spring loaded and set to a predetermined spring tenstion. They fatigue over time…Also you will want to pay close attention to any idler pulleys in the belt system…Alternator bearings have a tendency to momentarily elicit a loud squeak…then go away…and back again…the idler bearings do the same thing too.