Accelerator Cable Wont Go Back To Idle

[mondeman]

hi all,

i have a 2.5 lt 24v ecotech N reg mondeo which has just developed a problem. the accelerator cable is not pulling back to idle. the accelerator cable from the pedal goes into some contraption, then comes out of that and runs to the throttle body, 4 questions, whats the contraption called?

is it some kind of vacuum unit?

how hard is it to replace, is it something a novice DIY'er can do?

is it an all in one unit from the pedal into this unit and then on through to the throttle body?

thanks