2004 Chevy Malibu LT V6 car problems

2004 Chevy Malibu LT V6 battery light comes on during hard acceleration goes off as soon as I let go of the gas or it changes gears I have problems starting the car sometimes too not often though 140000 miles on the car what could be the problem?

Have someone check the serpentine belt for wear.

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Tester

will do thats whats it seems to be more than likely on what ive been reading up online

I would think that your tensioner is weak allowing the belt to slip, and needs to be replaced.

Yosemite