pfsantos

iTrader: (1)

I'm trying to help my buddy find the O2 sensor wire which seems non-existent in his TII as well as his spare TII wiring harness.
All we see is the knock sensor wire, Black in colour, coming out near the area of the rear housing. Looking at the wiring diagram, the wires for the knock and oxygen sensor are supposed to be Green w/Yellow stripe, and are apparently shielded to ground. At the computer, the wire is indeed this colour, going to the 2D pin at the computer. I'm also not sure whether the two sensor wires are supposed to be connected, although the multimeter is telling me that they are, when connecting the O2 pin at the computer to the knock sensor wire.

We've rebuilt about four or five engines together, I've resolderered and fixed CPU's, a logicon, warning lights, solved numerous electrical problems and disassembled RX-7's right down to the frame. I thought I knew something about these cars by now...but my experience is mostly on NA's

NZConvertible

You've misread the wire colour codes. It's GY (grey), not G/Y (green/yellow). The oxygen sensor wire goes straight to the ECU but the knock sensor wire goes to the knock control unit, and the wire from there to the ECU is LG (light green). There should not be a G/Y wire at pin 2D, but there is one two pins across at 2H.

The colour given for the knock sensor and oxygen sensor wires is misleading anyway, as this is the colour of the shielded part of the wire, which is inside the harness. At each end of the wire the shielded part stops and the black inner wire is what's visible. The oxygen sensor wire comes out of the harness at the same place as the BAC valve wires.

The signal wires should definitely not be connected, and I don't know how they could be.

pfsantos

iTrader: (1)

Excellent reply...thank you. I noticed that on one wiring diagram I had Gy and on another GY. I didn't see Grey listed in the colors, and started looking at the wrong wires. What you're saying makes sense now...