Fast idling after hot starting V8S

[Barkychoc]

If I park the car up, leave it a few minutes, then start it again it idles too fast, did it today and sat at a steady 2000 rpm.
After a short bit of driving it settles down and never plays up at all while its running, only at initial hot start. (It also settles down slowly if you just leave it running, then sits steady at 800rpm ish).

Engine is totally standard (if there is such a thing) 4 litre, 1992 pre cat.

Any ideas ?

Chris

[pies]

Is the stepper motor clean

[Barkychoc]

Yes gave it a clean the other day - was very sooty.
The metal cone on the end looks slightly rough once its cleaned up.

Is it possible its doing a cold start and pushing some extra fuel in there ?