what would make my ac comm. click back @ 4th when comm. is engaed ?
If I read this correctly, your A/C compressor is cycling rapidly, and it has caused 2 idlers to shatter. Might be dealing with more than just one problem here, A/C cycling is usually caused by low refrigerant pressure, have the system checked. Pulley shattering may have been caused by the belt tensioner bouncing caused by a weak tensioner spring, there is a special tool for measuring belt tension on serpentine belts, if you don't have the tool, they can check it while you are having the A/C checked.
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