Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Speed/Reference Mark Sensor
An inductive sensor on top of the crankcase serves as a speed and reference mark sensor. The sensor puts out signals for the instantaneous engine speed and crankshaft position via a separate pulse gear ring on the flywheel.
The sensor is mounted in a bore in the crankcase and cannot be adjusted. The sensor is identical with that used in type 944 vehicles. A wide tooth and a wide tooth gap of the pulse gear ring are used as reference mark for crankshaft position.
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:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.