03' 9-3 shakes during acceleration.
 

hi all,

i own a 2003 saab 9-3
my problem first started with a coolant tank lea wich i replaced.
now when ever a step on the gas too hard the engine seems to shake very hard, i've noticed it does this when the turbo needle goes all the way to the red area in the gauge.
please help, do i need a turbo?