Scenario: 1986 240DL 156K - Runs rough only at idle, otherwise good power and smooth running. Idles perfect (although a little high)with Mass Air Meter unplugged. Items done thus far include: Timing adjusted/ New plug wires/cap/rotor/all vacuum lines checked ok/throttle housing cleaned/ intake hoses ok/ intake gaskets and injector seals checked for leaks/ hall sensor checks ok.

Thanks in advance for the invaluable advise - its always a big help!