The tension is to tighten the serpintine belt. I can't find anything on how to loosen it on ask.com or YouTube. Anything could help at this point 2002 Malibu

its spring loaded to spring toward tight,one hand to pull on wrench the other to slide belt sideways off pully, remember the configeration or make drawing,for new install

belt not correct size

X2 on that wrong belt size. A ten year old tensioner should not be too tight.

I changed the alternator. Same belt the alternator us exact match from the last one. Same belt same size pulley. Still think its the belt?

What I ment was I changed out the alternator. And installed a new one. The new one is exact to the old one, pulley and all. Why would the belt be too small?? Same belt too. Isn't threre a way to loosen the belt for good? Like a way to adjust a pulley?

your stringing it wrong or its not in the little grooves

from what u say.. it could be a miss-routed belt or the alternator is slightly out of place.