Yup Idle control unit or valve??
I have 380sel too, but I believe this problem has been experienced by a few not only with the 116 engine. I had this problem about 5-6 months ago, disconnected the ICV thouroughly cleaned it out. Disconnected Idle control Unit, everything looked fine on it. So I think in my case the high idle 1100 to 1500 was the ICV.

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**A few Hondas etc... etc... Not Worth Mentioning**
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