Ford: 96 T-BIRD clanking noise, first hope, ac system

Question
the clanking noise coming from the front end of my t-bird happens every time i accelerate right away. if i go fast the clanking always appears and sounds ugly. it seems louder when i drive with the A/C on. the check engine light is always on, i had a diagnostic read and it was the vaccum. are these two DIFFERENT problems, or part of the same problem? what do you think is the clanking noise? if it helps any every time i shift into reverse it it makes a loud 'thunk' sound.    {4.6L V8, Auto trans.}

Answer
REENA

the thunk is probally your tranmission or drive train.the ac clutch on your ac system could be going bad also.i would take the car to a person or garage you trust,as trying to diagnois the problem from here is difficult at best.i would say your transmission or drive train or both are your problems i would look there first.hope this helps.

ken