1982 Mercedes Benz 300SDFACTORY OEM SERVICE PROCEDURE

All Models

The vacuum control valve is located on the fuel injection pump. It vents vacuum to atmosphere as throttle opens. With increasing engine load, vent size increases, decreasing vacuum signal to EGR valve. This reduces EGR as engine load increases. The Black plastic line leads to passenger compartment where vacuum is vented.

Factory Service Tools

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.