1985 Porsche 928 AutomaticFACTORY OEM SERVICE PROCEDURE

Test Equipment: Notes

  1. All sensor and ignition timing signals of Porsche vehicles can only be checked with engine testers recommended by Porsche. Since tester connections are made on vehicles differently depending on make of tester, always refer to supplier's instructions for correct test connections.
  2. Since curve shape and signal voltage ratings for inductive sensors are not always included in engine tester manuals, this article will supply you with some information for making correct connections.
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.