We have an '88 560 SEL with an idle problem. the problem is that idles at 1300-1500 in neutral and feels like you are brake torquing in drive. In troubleshooting for a vacuum leak carb cleaner and wd-40 revealed nothing.
I disconnected a vacuum hose at the driver side front of the engine and connected a vacuum meter (22 in hg) and the went to less than 1000 in park and 650 in drive. I took it for a ride and it seems fine. I have capped both sides of the line and we are driving it. What have I done?
Searching through the enteries I see things about an idle speed control box and cleaning it, also something about an air screw on a 4.5. Do I have these and should I be cleaning and adjusting them. I tried to follow the throttle linkage around but found that it apparently goes everywhere!
Any help would be greatly appreciated.