W116

Which Sourcelet or Guide Best for '80 300SD 116 Vacuum Troubles

The vehicle is a 1980 300SD, 116 Chassis with nearing 300K miles. My problems began with a slight delay in the engine shutting off with the key, and has progressed to no door locks and I have to raise the hood and manually shut the engine off. I have also noticed the engine is running rough at idle, but smooths out at about 1000RPM. I intend to troubleshoot the vacuum system, but can't tell from the descriptions which of the guides I should purchase: the vacuum door lock one, the my engine doesn't shut off one, or the larger, apparently more comprehensive diesel survivor's guide.

Chassis Model Number

W116

Forums

Diesel Engine Specific Aid

Read more about Which Sourcelet or Guide Best for '80 300SD 116 Vacuum Troubles

$9.75

615 616 617 Diesel Engine Fuel Injector Hard Line Clamp - USED

ONLY ONE LEFT: 200D 220D 240D 300D 300CD 300TD 300SD 1965 to 1985

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Leaking Oil Under the Dash Below the Instrument Cluster

Sure sign of a common problem - leak in oil pressure gauge actuator

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107 114 115 116 123 and Early 126 Torque Converter Drain Plug Washer Seal

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SVO WVO Three Way Brass Fuel Valve w/ 3/8 Hose Fittings

Old stock real brass made in USA. Limited to stock on hand

1980 300SD Cylinder misfiring while idling

The more I drive this old mercedes the better I like it. Recently I had new motor mounts installed and asked the mechanic that did the work about the engine still rocking and rolling in the engine compartment. He said that one of the cylinders was missing a hit while idling. When it's rev'd just a little it does just fine and on the freeways/hiways it just absolutely purrs. Could it be a glow plug or compression? Any hints would be appreciated.