Cannot find anywhere the description of the wires coming from the plug.
4 wires:
2 whites
1 grey
1 black.

Which one is the signal?

I assume the other 3 are just heater and does not matter where they connect.

The New Denso sensor has 2 black, 1 blue (signal) and 1 white.

I am trying to match them up.

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1999 Porsche 996 Carrera Convertible
1994 420E - SOLD
1986 300E - SOLD, what a car
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