Porsche 951 Crank sensor.

[Jayson D]

I'm getting some mixed info and looking for some Guidence,   crank reference sensor on a1986 porsche 951 is the sensor in question.   I have a white, black, and shield in my loom trigger 1.    Should I use the shield pin in the sensor to connect the shield from the loom? Or tag it to shield/gnd? Or not connect it at all?       I can see reasons for all 3 and can't determine what's correct.   Any info would be great!   And if anyone has a base tune for said car I would happily pay for it

[Adamw]

The two with the 960 ohm resistance between them are your ground and signal.  The ground connects to the white wire and the signal to the black.  If you dont have any documentation to show which is +/- then sometimes it can be determined with a basic multimeter test - I will explain that in more detail below.

The third pin is the shield for the sensor pigtail, connect this to the bare drain wire in the link loom.

Multimeter test to determine VR sensor polarity:

Set multimeter to DC mV.  Connect the positive MM lead to one of the pins and the negative to the other.  Hold a piece of metal touching the sensing end of the sensor - something like a steel rule or spanner works well.  Quickly pull the metal object away from the sensor while watching the multimeter.   If the multimeter shows negative voltage while you move the metal away then the multimeter leads are indicating the correct wiring polarity (i.e the pin that the red lead is connected to is your + signal wire).  If it shows positive voltage then wire the sensor opposite to how the multimeter was connected.