No Idea.
But part of the system is mechanical. It is situated next to the throttle body, and incorporates a bellow and an adjustable rod in a plastic holder. The rod can be moved in the holder to provide the right amount of travel. Usually it has been painted originally where it was adjusted.
I would, as a first port of call, check here to see that there is no mechanical interference, and all connections are OK.
Then I would check the speeder cable and its free travel and lastly that no carpets or mats are interfering, which I doubt.
If that does not work, then you have an electrical problem.
If you can't fix a problem with a hammer, then it is usually electrical.
