hybrid_KJ

How do I wire the one wire cx o2 sensor to the four wire? I did a search and could not find a good enough answer.

Thanks
Kevin

EE_Chris

Your question isn't very clear.

What exactly are you trying to do....install an OBD-I engine/ECU into an OBD-II chassis?

Got a Helms for you car?

jetli6969

If your running an OBD I computer (and a chipped P28 would be OBD I), you'll need an OBD I 4-wire o2 sensor. Convering over shouldn't be to bad, but you will need to add some wires. I'm assuming you are re-using your stock CX's engine wiring harness on the new motor. The o2 sensor will have 4 wires coming out of it: Green/White, White, Orange/Black and a Yellow/Black. Here's the ECU pinouts

Green/White - D22
White - D14
Orange/Black - A6
Yellow/Black - B1 (or a switched 12v)

You can re-use the existing single wire O2-sensor's 1 white wire as the new 4-wire O2 sensors White wire (they both go to D14). You should be able to run the Green/White wire to the big 14 wire connector on the passanger side of the engine bay. There should be a Green/White wire on the in-car side of the harness and a brass plug on the engine side. The Orange/Black connection can also be made at that same connector. It will go from the Orange/Black wire at the 4-wire O2 sensor to the Orange Black wire coming out of the in-car harness at the 14 plug connector on the passanger side (again, the engine side of the harness will have no wire sticking out of it, just a brass cap/plug). The Yellow/Black will have to be run either to B1 on the ECU or any other 12v swtiched source (B1 is just that).

If the in-car harness doesn't have the color wires you need (only the 92's have all the wires regardless if the car orignally had VTEC or a 4-wire O2 sensor or not, later models might not have these extra wires in the in-car harness), they may simply not exist and you will have to run the wires all the way down to the ECU yourself (if your not sure about all of this, doing that might not be a bad idea anyway). Good luck. Seeya.

PS got this from ANDY at H and A.net, but very clear instructions. i just got done on my car.

hybrid_KJ

thank you that is exactly what I was looking for.