Making a harness extension for the rear 02 sensors so I can route it under the beauty cover as per the factory
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I’ve been wanting to do this - I have all of the male and female connectors, just haven’t found a minute to get wiring. Do you have a cheat sheet on which wires you bought?Originally posted by maupineda View PostMaking a harness extension for the rear 02 sensors so I can route it under the beauty cover as per the factory
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Yeah, I have a few sets of sensors I can pull the wiring from but wanted to find the wiring separate from cutting through a few O2 sensors… fun!Originally posted by maupineda View PostNo, I have not made one. But will do one as I splice them and join them.
i have re routed the engine side loom to the plastic holder and taken the exhaust off
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I have traced the pins, the tricky ones are the white ones, but I am almost certain they don’t have any polarity, anyhow, this is how they are from the factory, the numbers below are the PIN numbers on the connector sideOriginally posted by davidinnyc View Post
I’ve been wanting to do this - I have all of the male and female connectors, just haven’t found a minute to get wiring. Do you have a cheat sheet on which wires you bought?
1 - white wire. Heater element
2 - white wire. Heater element. This lines up with the sensor part number on the sensor body
3 - gray wire. This is the signal wire to the DME
4 - black wire. This is the sensor element ground
the white wires really just close the loop to the heater element which is nothing but a resistor, same in principle as a light bulb filament.
I am basically making one sensor harness out of two, to join them I am using crimped terminals isolated with heat shrink tubes. To make it easier to myself I colored white wire for pin 1 with a black sharpie so I know which is which without having to removal the harness protective sleeve
Last edited by maupineda; 02-16-2026, 05:53 PM.
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things are happening.
we got a good rain on sat that washed all the salt off the roads.
gave the car a good wash/vac on Sun, and put new Motul XPower oil in with Mahle filter yesterday. Ordered an AC o-ring kit to hopefully get that working, and a new blower motor/resistor to put an end to the fan squeeking. Then ordered new MPS4S to replace the supersports I put on the car in 2010. Hopefully I can get the ohlins R&T installed in the next ~week. So many big things getting checked off the list this year the car is finally going to be put back into real service after a decade of sitting on the sidelines.Last edited by tnord; Yesterday, 01:25 PM.
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