RED guy

Hey guys
My 95 GT (AUTO) Vibrate like crazy at 1300 to 1500 RPM
and some time when the car want to shift
The belt tensioner is bad also doing a noise since i bought the car,a mechanic said that the harmonic damper is damged!!
What do you guys think??
please help i cant drive it like this

Stolen94GT

Your mechanic is a smart guy. Have a 94GT with automatic trans. and had the same problem. Left work one night and pulled out onto the road and got a heavy vibration on acceleration.By the time I got home 32 miles later the car was barely driveable.Got under the car the next day and found my harmonic balancer outer ring was loose and it had spun out of position. You can turn it with your hands, it's trash. Your local auto parts store has them for about 55 dollars and up. Not hard to change, but don't try to tap it on with a hammer or you will ruin the brand new one. Also the belt tensioner pulley bearing is probably bad and fairly cheap.