[V8] Two seemingly stupid questions - 02 sensor and weight

[Buchholz, Steven]

... since it is not standard, I'm a little surprised that Bruce did not provide some direction here ... 

My recommendation ... (made without any direct knowledge of the internal grounding configuration of the 4-wire sensors)

First, take an ohmmeter and measure the resistance between that grey wire and the case of the OXS.  If you measure something very close to -0- ohms, then you could very well just ignore the grey wire ... and would recommend that you do exactly that.  

I suspect that you will find a high resistance between the case of the OXS and the grey wire ... high being defined as anything more than 10-100 ohms ... in that case you need to connect the grey wire to ground for the ECU to get a usable signal from the OXS.  My recommendation for the best place to connect this ground is at one of the bolts on the back of the engine below the left distributor which attach the ground lugs from the ECU.  

Steve B
San José, CA (USA)
> 
> Grey wire?  It's an additional ground.  Use it.
> 
> >
> >   1) got the 4 wire 02 sensor from Bruce.  What do I do with the
> > grey wire - just cap it?