Idle goes up as temp goes up

[Lammers]

My idle goes up by about 200 rpm from cold to warm.
Currently I have it starting at 600 rpm so it reaches 800rpm when warm.
If I set the idle correctly at 800 at cold, it will start surging once the idle goes over 1000rpm because it's now warm. Any ideas why the idle goes up like that?
85' 911 3.2

[wazzz]

Make sure your ICV is functional. Switch the ignition on, don't start the engine, go to the engine compartment and listen. You should hear the ICV humming. While this is not sufficient to consider the ICV good, it is a good start. If it's not humming, the ICV or its driver is not functional.

Next make sure you set the idle at 800 only when engine is fully warm, and by following the procedure to temporarily cancel the ICV function. Use a jumper wire to shunt terminals B and C on the round plug under the black plastic cover on left hand side of engine compartment.