hi guys need your help, recently bought a focus st170 only after a few months developed this problem where the revs are hanging when you rev it or when you change gear really slow at dropping between gears any idear guys ?

 

try the focus st170 owners group on facebook. someone will be able to help

 

Sounds like a sticking idle control valve.

 

Try cleaning your idle speed control valve out and see if that cures it. My old fiesta zetec s always did this and a good clean very 6-8 weeks used to sort it.

 

Idle means just that. I would have a go at cleaning the throttle body, as from you're description it might be a sticking butterfly valve inside it.