1991 BMW 850i AutomaticFACTORY OEM SERVICE PROCEDURE

Check Function

With engine at operating temperature and ambient air temperature at 64-82Β°F (18-28Β°C), intake air temperature is at 122-158Β°F (50-70Β°C). A display below - 40Β°F (- 40Β°C) indicates a break in the temperature sensor or in the supply wire to the DME control unit.

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.