Why does my o2 sensor have one wire

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alicbr
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Why does my o2 sensor have one wire

Postby alicbr » Sat Oct 13, 2018 8:58 am

I have a 1995 s14 with s13 red top sr and can’t figure out the o2 I need please help


amc49
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Re: Why does my o2 sensor have one wire

Postby amc49 » Sat Oct 13, 2018 11:18 am

Earlier ones if correct only need one wire the output, O2s make their own voltage. Later ones add a heater circuit to heat them faster to lower emissions.

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PapaSmurf2k3
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Re: Why does my o2 sensor have one wire

Postby PapaSmurf2k3 » Mon Oct 15, 2018 12:49 pm

What's the problem?
Do you have a 1 wire O2 sensor and your harness is for a 4 wire?

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Hijacker
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Re: Why does my o2 sensor have one wire

Postby Hijacker » Tue Oct 16, 2018 6:43 am

Red top harnesses have heating elements in the O2 circuit, so it has an additional 2 wires. Only one wire is actually signaling to the ECU. It's been a while and I can't remember the wire colors off hand, but you only need to connect your single wire O2 sensor to the signal wire.


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