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1G O2 sensor help 1g

Kyky819

Proven Member
53
7
Aug 31, 2018
Otis orchards, Washington
I just picked up a clean 1g and I need to add in a factory O2 sensor. Right now it has a PLX multi gauge wide band wired into pin 4 I believe(white wire red square) and the wide band o2 is in the O2 housing. I’m having a hell of a time finding the factory plug. The only plug anywhere near the area doesn’t fit my new O2 sensor. Do I have to wrong sensor or is the plug just non existent?

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DSMPT

DSM Wiseman
1,999
1,553
Jun 12, 2014
Japan / Mexico, Arizona
Usually you don't need a factory O2 sensor if you have a working PLX wideband gauge w/ a sensor. The PLX WB unit has an analog 1v output that can simulate the factory O2 sensor, so you just connect the analog output to pin #4. Which PLX unit do you have?
 

Kyky819

Proven Member
53
7
Aug 31, 2018
Otis orchards, Washington
Usually you don't need a factory O2 sensor if you have a working PLX wideband gauge w/ a sensor. The PLX WB unit has an analog 1v output that can simulate the factory O2 sensor, so you just connect the analog output to pin #4. Which PLX unit do you have?
It’s a plx multi gauge with the red box. My tuner said he won’t tune on simulation so I was going to move the sensor wire from pin 4 to the egrtemp pin and run the wideband O2 in the down pipe
 

DSMPT

DSM Wiseman
1,999
1,553
Jun 12, 2014
Japan / Mexico, Arizona
So you have ECMLink and your tuner doesn't want to turn on the NB simulator, that's what you say? What I was telling you is you take a 1v narrow band signal from the PLX red box and you can connect the WB signal to any available 5v input if you have ECMLink or standalone ECU. In this way, you can keep the WB sensor in the O2 housing and you don't need a factory O2 sensor neither turn on the NB simulator in ECMLink.
 

Kyky819

Proven Member
53
7
Aug 31, 2018
Otis orchards, Washington
So you have ECMLink and your tuner doesn't want to turn on the NB simulator, that's what you say? What I was telling you is you take a 1v narrow band signal from the PLX red box and you can connect the WB signal to any available 5v input if you have ECMLink or standalone ECU. In this way, you can keep the WB sensor in the O2 housing and you don't need a factory O2 sensor neither turn on the NB simulator in ECMLink.
Ya I talked to him yesterday and he said I have to have the stock in the O2 housing and the wideband in the O2. I have a innovative lc2 so I’m not to familiar with the plx. And yes it’s on Ecmlink v3
 

DSMPT

DSM Wiseman
1,999
1,553
Jun 12, 2014
Japan / Mexico, Arizona
Ya I talked to him yesterday and he said I have to have the stock in the O2 housing and the wideband in the O2.
Do you have two O2 sensor bungs on the O2 housing or somewhere close? If not you would have to make one more to do that.
If you have two already, just look for the stock O2 sensor plug that is a black round w/ 4 pins (Please refer the link below). If it hasn't been cut, you can probably find it somewhere under thermostat housing (It's coming from the same bunch of wires for the coolant sensors on thermostat housing) and install the factory O2 sensor. And then connect the WB signal from the PLX red box to your desired input and assign the input pin in ECMLink. I think that's what you want to do.

I have a innovative lc2 so I’m not to familiar with the plx
What you do would be basically the same.
 

Kyky819

Proven Member
53
7
Aug 31, 2018
Otis orchards, Washington
Yes I have 2 already so the wideband is no problem hooking up. I just can’t find the physical oem connector. That plug in the above photo is the only free plug under the thermostat housing and it’s bunched together with the coolant temp wiring. I’ll go out today with a multimeter and see if it’s just a different plug type
 

19Eclipse90

DSM Wiseman
5,145
983
Sep 29, 2003
OKC, Oklahoma
Definitely do some wire tracing, but the previous owner could have wired in a connector for a 2G-style O2 sensor.
 

1990TSIAWDTALON

Moderator
9,128
4,964
Nov 14, 2013
Independence, Kansas
The factory harness side plug should be in or very close to the 2 circular clamps that I circled in RED, under the thermostat housing.
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Kyky819

Proven Member
53
7
Aug 31, 2018
Otis orchards, Washington
The factory harness side plug should be in or very close to the 2 circular clamps that I circled in RED, under the thermostat housing.
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Oh ya I know that’s where it’s supposed to go but there’s nothing there at all. That’s why I’m wondering if it’s just not there at all. Any idea what that plug is I’m holding? Tried searching around but couldn’t find anything
 

1990TSIAWDTALON

Moderator
9,128
4,964
Nov 14, 2013
Independence, Kansas
I haven't ever seen that plug under the hood of my 1g cars, but I studied it and scratched my head trying to figure out what it was. It resembles a 2g fan connector for the drivers side, like in THIS picture from Snowboarder though.
 

19Eclipse90

DSM Wiseman
5,145
983
Sep 29, 2003
OKC, Oklahoma
The gray connector you have pictured is not a factory 1G connector. Hence my last comment. The square 4-pin connector appears that it could match up with a 2G-style O2 sensor, however. And if the wires are bundled together with the coolant temp sensors, it would make sense that is what has happened.
 

Kyky819

Proven Member
53
7
Aug 31, 2018
Otis orchards, Washington
Okay just went out and tried my 2g O2 and still wasn’t even close.

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Kyky819

Proven Member
53
7
Aug 31, 2018
Otis orchards, Washington
Okay think I found it… it looks like it’s a Toyota/Subaru plug. Will this work if I just get the corresponding sensor?

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19Eclipse90

DSM Wiseman
5,145
983
Sep 29, 2003
OKC, Oklahoma
That's a new one for me! LOL

I have no idea whether those sensors would be compatible so I cannot help there. All I can say is if it were my car, I'd put a DSM sensor + connector in there.

Good luck!
 

Kyky819

Proven Member
53
7
Aug 31, 2018
Otis orchards, Washington
Okay I tracked the wiring back and I indeed have 2 blacks 1 red 1 white. I know it would be easier to get the 1g plug but I do have a 2g plug and O2 sensor just sitting here. Will the 2g wire up to a 1g?
 

19Eclipse90

DSM Wiseman
5,145
983
Sep 29, 2003
OKC, Oklahoma
Yes.

B-26: Oxygen Sensor

B-26: Oxygen Sensor

@brads has informed me that the OEM 1G O2 sensor is discontinued. JNZTuning has recommended using the 2G O2 sensor if OEM equipment is desired. If that is something you want to consider, the harness connector must be changed to match the sensor. That connector can be had here: NMWP4F-B
Due to a lack of good, new supply of this original connector, I went ahead and took the above advice and swapped to a 2G connector to utilize the 2G O2 sensor. In order to do so, the wire positions will slightly change. The wire pin orientation in the original connector, as noted in the picture, is as follows with the latch mechanism on the top of the connector and looking at the harness connector from the wire side of the the connector:
[xx]
[01][02]
[03][04]

Original 1G Wiring Positions
01 - White (To ECU)​
02 - Little Black (Thermistor / Heater Ground)​
03 - Red (Power)​
04 - Big Black (Sensor Ground)​

New Wire Positions to Match 2G Sensor
01 - Red (Power)​
02 - Little Black (Thermistor / Heater Ground)​
03 - Big Black (Sensor Ground)​
04 - Red (Power)​
 

Kyky819

Proven Member
53
7
Aug 31, 2018
Otis orchards, Washington
OK I’m a little confused. there is no ECU wire on the 2G connector but the 2G connector has two hot leads. are one of the powers on the 2G connector supposed to be for the 1g ecu?
xx]
[01][02]
[03][04]

Original 1G Wiring Positions
01 - White (To ECU)
02 - Little Black (Thermistor / Heater Ground)
03 - Red (Power)
04 - Big Black (Sensor Ground)

New Wire Positions to Match 2G Sensor
01 - Red (Power)
02 - Little Black (Thermistor / Heater Ground)
03 - Big Black (Sensor Ground)
04 - Red (Power)
 

19Eclipse90

DSM Wiseman
5,145
983
Sep 29, 2003
OKC, Oklahoma
That's my error. Thank you for catching it and my apologies for any confusion. Pin 4 would be the white wire to ECU.

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Kyky819

Proven Member
53
7
Aug 31, 2018
Otis orchards, Washington
That's my error. Thank you for catching it and my apologies for any confusion. Pin 4 would be the white wire to ECU.

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Ah thanks so much! I was kinda guessing it was the odd one out but I want to double check
 
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