Pontiac Repair: tensioner rattle w/ air cond. on, unrelated problem, belt tensioner

Question
I am on my third belt tensioner(in fifteen months)on my '94 Firebird 3.4 VIN S.  The tensioner rattles at idle with the a/c compressor on, and the tensioner will eventually snap off after several months of rattling.  I just recently replaced the compressor for an unrelated problem, but the rattle still persists. Is there a service bulletin for this problem?  Or is there something else I'm overlooking.  
Thank you in advance.

Answer
Hey Joe:

I would take a look athe the idler pulley first and if that seems tight and it's running true then I would replace the tensioner and belt with original equipment parts not aftermarket. I don't recall and bulleting on these. make sure the surface the belt tensioner attaches to is clean and free of corrosion and if this tensioner has a dimple in it to line up withe the moun ting surface make sure the hole the dimpel goes into is not hogged out or distored in any way.. I don't remeber how this one is attached. I want to say it just has 2 bolts that attach it to the engine. It's been a looongg time since i worked on one of those! Good luck :)