I have a 1987 560sl, and about a month ago it started to idle at1800 rpm with no warning! the next morning it wa back to normal, no problems.
Last saturday (halloween) it started to idle high again, only this time it keeps on doing it. I checked the high voltage saftey relay, fuse ok, solder joints appear to be good, now I removed the idle speed control module from behind the glove box. Any body know what I should check on this module, or could something else becausing the fast idle? Any help is greatly apprecited, anything to avoid the dealer!

Thanks much,
-ddayme