Greetings I am a new owner of a nice old 560sl. The check engine light just came on. The car runs fine (good smooth idle, plenty of power etc).
I do have a smell of gas that smells like its running rich but maybe they smell like that when started?

It is orignaly from California & has the push button code reader on the 8 pin diagnostic port. I have read many posts using the search feature but nothing quite solves my issue.

The code I get after holding the button down for a couple seconds is "4 blinks" Does anyone know that code? Also I noticed that this device (pictured) makes a buzzing noise if the car is running & when just the key is on engine off it still buzzes. The part I "think" it looks like is the idle control valve. The idle is at 7,000 rpms at idle with it in gear & 10,000 rpms in park (this seems high eh?)

Thank you for any input.
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