1985 Mercedes Benz 380SLFACTORY OEM SERVICE PROCEDURE

O2 Sensor

Temperature of O2 sensor must be below 572Β°F (300Β°C). Check on/off ratio displayed on tester. If reading is constant 50%, O2 sensor is good and test is complete. If reading is constant 92%, O2 sensor is shorted out and must be replaced.

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.