1985 Porsche 928 AutomaticFACTORY OEM SERVICE PROCEDURE

Octane Loop

The ignition performance graph can be retarded approximately 3Β° via a plug connection on the EZF control unit plug. This way the engine can use lower octane gasoline. Standard is with plug disconnected. With the plug connected ignition timing should be minus 3Β° at full load or high partial load.

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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.