1990 BMW 535iFACTORY OEM SERVICE PROCEDURE

Idle Speed & Ignition Timing

Ensure idle speed and ignition timing are set to specification. For adjustment procedures, see ADJUSTMENTS article.

IDLE SPEED & IGNITION TIMING SPECIFICATION

Application Idle RPM Timing Degrees BTDC @ RPM
325 Series 720-800 2 @ 840
525i 650-750 0 @ 700
535i & 735i 750-850 10-16 @ 750-850
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.

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