i have 2001 3.0 coupe and when i step on the gas it hesitates what is causing this also sometimes on start up it wants to die like its not getting fuel or something it makes a wierd noise coming from the rear like its the fuel pump and just today two times in a row i started it up and it just started squeaking so bad for maybe little more than 5 seconds never sqeaked before possibly the belt going bad or the tensioner?????????? has anyone else had this problem and if so what are the solutions to my problems any help would be great

thanks
sebastian