My '86 560sl occasionally idles at 1700rpm. The problem is intermitent & I've found that if I remove the wire from the idle control valve, and then put it back on, the car's idle returns to normal. Today the idle seemed to be OK until I would come to a stop. The idle would at first start out normal (10 seconds or so) & then bump up. I'm not certain if the idle increased when I pushed on the brake since I can't get the problem to repeat itself by design. Does this sound like a problem with the amp? Is the idle system a vacuum system and could a leak be the problem? The reason I don't think it is is that when I remove & replace the valve wire the idle goes back to normal. Thanks for any advice. Mike