Unround idle after push operation

Hello, my S6 spins again and here I have always received nice help.So I have had the following problem for a few days.After downhills I have large fluctuations in idle 200-1100 revolutions.I changed the idle control valve but there was no change.But this problem I only have after stopping in sliding mode otherwise the engine runs clean.runners and caps are also new some hoses ( crankshaft throttle valve ).I type that the throttle pot is not io.Is this stored in the error memory?Has one an ide