O2 sensor wiring and readings??

[alain]

I just installed a new Denso O2 sensor with 4 wires (BLACK, BLACK, WHITE, BLUE) for my 95 eagle talon. The wires coming from the ECU are RED, BLACK, WHITE, YELLOW. Using a voltmeter, RED=12.2V, BLACK=.11V, WHITE=.12V, YELLOW=.11. I figured RED was battery voltage, WHITE was signal, BLACK and YELLOW ground. They told that the o2 sensor BLACK wires was heater, WHITE was ground and BLUE was the signal to ECU. So I connected the ECU cables to sensor cables as follow: RED -> BLACK, BLACK; BLACK,YELLOW -> WHITE; WHITE -> BLUE.
Is this wiring correct?

The sensor, when the car is not moving, regardless of the amount of throtle at neutral and from just starting the engine to 15 minutes later, fluctuates from .10 to .20. I rich the AFC and nothing happens. With the car moving at 2nd, 3rd and applying throtle it does changes but doesnt cycle between rich and lean .1 to .9 as it is supposed to.

Is this normal?

And last question?

Some ppl tell me the target readings for any rpm is .5, others tell me .97... which one is it?
What is too lean.. what is too rich??

 

[justin0469]

Any time you are not at WOT, the front o2 should cycle from lean to rich. Front o2s range from 0-1V. 0 being lean and 1 being rich. The only time it would not fluctuate is when the ECU is in open loop. The ECU does that only when you are at WOT, so far out of your fuel trims it doesnt know what to do with it or if you hooked up your sensor wrong. Next time dont get a universal one, get one made for the car.

From Sensor:
White - o2 signal
Black - Heater
Black - Heater
Blue - Ground

From ECU:
White - o2 signal
Yellow - Heater -
Red - Heater +
Black - ground

so i would say it goes like this
White to White
2 Blacks to red and yellow
blue to black

polarity for the heater shouldnt matter, if it doesnt work, reverse it.

 

[idt512]

Front o2s range from 0-1V. 0 being lean and 1 being rich.

From Sensor:
White - o2 signal
Black - Heater
Black - Heater
Blue - Ground

From ECU:
White - o2 signal
Yellow - Heater -
Red - Heater +
Black - ground

so i would say it goes like this
White to White
2 Blacks to red and yellow
blue to black

polarity for the heater shouldnt matter, if it doesnt work, reverse it.

good info there, but is the voltage range of the rear o2 sensor any different? I just ordered an o2 sensor for the front but i received a rear sensor instead, rather than returning it i was wondering if i can just cut off my OEM plug and solder it onto the new sensor

 

[justin0469]

they are both narrowband sensor so yes the range is the same, as long as the hole they go in is the same size it should work as far as i know.

For BOTH of you, cut the factory wires on the sensor side of the connector. DO NOT CUT OFF THE CONNECTOR PLUG! next time you replace it, then you can just unplug the side you wired and just get one that plugs right into the stock connector.

also if this helped either of you, adding to my rep would be appreciated

 

[MitsuBoost]

just what i was looking for... anyone have the pinouts and color codes for the rear sensor?

 

[justin0469]

im pretty sure the colors are the same, just the sensor wire goes to a different spot in the ecu

 

[idt512]

polarity for the heater shouldnt matter, if it doesnt work, reverse it.

ok i just got done with my install, however i need to note that the heater wires DO matter, and its hard to distinguish which is + or - since they're both the same color... anyway i had it backwards at 1st and it set of the CEL, i probed all the wires and they all seemed correct so i suspected the heater wires, and sure it enough the CEL went away

BTW, how do you add credit to ones rep other than buyer/seller feedback? it was indeed very informative, thanks a bunch

 

[justin0469]

ohok, i wasnt sure thats why i said if it doesnt work reverse it and to give someone rep (its not buyer/seller, more like for good info) click on the pic of the scales next to "currently online" or "currently offline" under the persons name next to the post

 

[alain]

Any time you are not at WOT, the front o2 should cycle from lean to rich. Front o2s range from 0-1V. 0 being lean and 1 being rich. The only time it would not fluctuate is when the ECU is in open loop. The ECU does that only when you are at WOT, so far out of your fuel trims it doesnt know what to do with it or if you hooked up your sensor wrong. Next time dont get a universal one, get one made for the car.

From Sensor:
White - o2 signal
Black - Heater
Black - Heater
Blue - Ground

From ECU:
White - o2 signal
Yellow - Heater -
Red - Heater +
Black - ground

so i would say it goes like this
White to White
2 Blacks to red and yellow
blue to black

polarity for the heater shouldnt matter, if it doesnt work, reverse it.

Thanks a lot for the reply... Even though it is working, I must have it wrong connected. I currently have both black from sensor connected to red!.

 

[alain]

I just installed a new Denso O2 sensor with 4 wires (BLACK, BLACK, WHITE, BLUE) for my 95 eagle talon. The wires coming from the ECU are RED, BLACK, WHITE, YELLOW. Using a voltmeter, RED=12.2V, BLACK=.11V, WHITE=.12V, YELLOW=.11. I figured RED was battery voltage, WHITE was signal, BLACK and YELLOW ground. They told that the o2 sensor BLACK wires was heater, WHITE was ground and BLUE was the signal to ECU. So I connected the ECU cables to sensor cables as follow: RED -> BLACK, BLACK; BLACK,YELLOW -> WHITE; WHITE -> BLUE.
Is this wiring correct?

The sensor, when the car is not moving, regardless of the amount of throtle at neutral and from just starting the engine to 15 minutes later, fluctuates from .10 to .20. I rich the AFC and nothing happens. With the car moving at 2nd, 3rd and applying throtle it does changes but doesnt cycle between rich and lean .1 to .9 as it is supposed to.

Is this normal?

And last question?

Some ppl tell me the target readings for any rpm is .5, others tell me .97... which one is it?
What is too lean.. what is too rich??

Sorry to ask this again... I am not clear about this... what is the target readings for any rpm .5 or .97? Does it changes from rpms? Right now I can see ~ .90 to .98 at 3k 4k 5k 6k 7k in 3rd, 4th and 5th gear

 

[justin0469]

with both those wires hooked up to red, your heater element probably isnt working. so it eventually heats itself up from exhaust.

The front o2 readings should bounce from low to high to low to high etc. while at idle and while just cruising. the only time the o2 should stay constant is when you have it floored (wide open throttle WOT) or when it is so far out of the fuel trims that the ECU does not understand what to do. The reasons the o2 goes from low to high (lean to rich)continuously is to overall have the best average gas mileage. RPM does not effect it, only throttle position. an example of what your o2 should be .04 .94 .03 .93 .07 .94 etc