O2 sensor wiring

[yodafrick]

Does anyone know the wire colors coming off the o2 sensor side of the factory plug? I have a LCEngineering header that I recently installed on my 87 runner and am wiring up the o2 sensor. Just need the schematics to wire it in properly. Thanks

I could also cut the connector and rewire, but it seems like there are only two wires going into the connector on the harness side and the o2 sensor has four wires connected to it. Thanks again.

 

[pappy]

Me thinks you have the wrong sensor. Don't let that discourage you.

My 1985 has a one wire sensor. In later years Toyota installed heated sensors which were mostly three or four wire (my 3FE is four). On my Thorley header the Ox sensor only read from one pipe and I really had a problem passing the sniff test at idle. The presumption was that the sensor was not staying hot enough. My solution was to install a three wire heated sensor down stream on the collector.

I don't have a wire diagram for your year. Usually a blue or blue/white wire will be the signal wire and the brown is ground. You will need to match that up with the four wire sensor.

 

[yodafrick]

Thanks man. That quite possibly be the case. I bought a complete 89 pu w/ the exhaust and swapped it onto my pu, then recently the runner. I'll have to dig through the pile o parts for the stock manifold and swap sensors and lengthen the wiring. I was just hopin to keep the o2 sensor intact cause we all know how much fun they are to remove...
Thanks again.

 

[KLF]

You definitely have the wrong sensor. I installed the same exact header last Fall on my '87, I also had to extend the wire for the O2 sensor since it's now down in the section in front of the cat. I used the wire that came with the header, soldered and heat-shrinked. I extended the harness, not the pigtail on the sensor.

 

[yodafrick]

Thanks Ken. I'll have to change out the o2 sensor. I am assuming the current one was from the 89 the header/exhaust was originally purchased for.

 

[willie64]

I have a similar problem. I recently bought what is an 85 that the PO rebuilt. He replace the wiring harness and ECU with an 88. The problem is that the pathway for the wiring from the sensor location before the cat was circumvented by routing the wires up through the shift boot and routed to the ECU from there. After replacing the exhaust and o2 sensor I was still getting CEL codes for o2 sensor. I then removed the ECU cover to find that the wiring was disconnected/ poorly connected. I am now finding it confusing as to which wire connects to what. They don't seem to go same color to same color and I could use the extra gas mileage. I've posted on other sites and haven't received any good advice. Some seem to think that the 88 wire harness is incompatible, but everything is working well and I'm convinced if I can get it wired up correctly I would be good to go. Any help would be greatly appreciated.