Re: idle and response issues
First check the rubber hose from the throttle body to the MAF sensor for breakage. A temporary fix would be taping it up with duct tape after cleaning it with a cloth dampened with solvent. Also check for any water below the ignition coils especially on cyl.1.
If your car is post 1998 with a plastic valve cover your idle speed actuator could be to blame. First ascertain that the throttle does not park on the accelerator cable, but on the proper stopper which should never be tampered with. Go to a garage with Alfadiag or Fiat examiner and after getting any fault codes checked and rectified(eg. lambda sensor), 'reset parameters' and then 'reset idle speed controller', preferably after the throttle body has been cleaned. If this does not solve the problem the idle speed actuator will have to be changed especially if the printed circuit cover is missing. You will have to again perform a reset after this. Even after doing all this, you could still have a faulty MAF and/or dirty injectors and even rotten spark plugs which will make the performance sluggish.