My vehicle idles at about 495 rpm warmed up (with a/c on). Is there a way to mechanically (vs. electronically) adjust idle speed to around 600 rpm?

It doesn't quite shudder or stall or anything like that but you can barely feel, for lack of a better term, an impending shudder or an ever so slight quiver or tremble if you will.

I'd like to bring it back up to spec.

If this can only be done electronically, how does one go about it?

Thanks.

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Rainmaker
93 500E, 43k mi, Pics of upgrade parts
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