I have a '96 Honda. The O2 sensor has gone bad so I replaced it with a Bosch universal O2 sensor myself. (No exact fit sensors could be found around here.) The check engine light is still on. I'm afraid I didn't match up the wires correctly because the instructional diagram was not very up-to-date. I mean the new sensor has 2 white wires, 1 black, 1 gray. I have to match these up to the original, which has 1 green, 1 white, 1 black and dammit, I'm not sure, but I think 1 red. (Should have thought about this more before I typed this post. It's been over two weeks since I put it in.) Anyway, I don't suppose anyone here could help me with this could you?

 

I believe on the OE Denso O2 sensor:
White wire - signal
Green wire - ground
Black wire - heater
Black wire - heater

All Bosch 4-wire sensors have:
Black wire - signal
Gray wire - ground
white wire - heater
white wire - heater

So in conclusion:
Old white wire to new black wire
Old green wire to new gray wire
Old black wire to new white wire
Old black wire to new white wire

You can check on Bosch site to confirm their wire color code.

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