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So you wired in a 2 wire sensor to the four wire plug and left the other two wires to run the heating element in the old sensor?

would it not have been way easier to just get the correct sensor?

 
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The sensor is the correct one just the heating element is not working.
No. I would have spent more time "getting" new sensor not to mention the cost of it.

 
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Ok maybe mention that in the original post,hard to tell what you did with no context or description for the pictures

 
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So now you have a O2 sensor that has no heater function at all and a small toaster attached to an exhaust. OoooooooKay I guess that is one way to do it, wouldn't be a route I would consider. So do you have any codes now? O2 slow response? Heater circuit codes due to incorrect resistance?

 
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I am sorry I thought it was clear since you can’t purchase an old sensor.

 
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I didn’t check how many watts is the heating element. My guess is 5-10 Watt. Hardly a toaster, a bulb is more powerful.. No codes whatsoever even in the freezing cold those days. Why would I have incorrect resistance? The heating element in the attached old sensor has the same specs.

 
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How long (mileage) has it been running with this modification in place?
The sensor inside the cat isn't working as intended. I speculate could set a code for slow response or maybe high/low voltage, or even a cat code P0420 because that rear sensor has lost its internal heater.

 
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At least 120 mi. The real test is the number of cold starts. In few minutes the temperature around the sensor exceeds the temperature of heater element.
I am monitoring the Voltage and Short Term % Data. Looks OK. What do you think?

 
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Does your car have to pass any emissions testing?

What you've done is not a proper repair no matter how you look at it. You fooled the computer and it might be happy for the moment but that's it.
Why didn't you just install a new correct sensor?

 
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You are right. I am fooling the computer for the first few minutes every time I start the car. After that the sensor is hot with or without heater element. I can bet you haven't seen such a wild repair. Emission is due Sept. 2020. In spring when the weather warms up I will get one properly working O2 sensor from the junk yard. After your post I am curious to compare the graphs. No way I am paying for downstream O2 sensor.
Thanks

 
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It should be far cheaper than an AF sensor

 
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Up and Downstream NTK are the same price $45 in Autozone. I did replace the upstream with new one of course,

 
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Now I am hooked. I want to see and compare the graphs of sensors with and without heating element. I suspect the heating element system is BS. It can barely help warming up the sensor. It takes minutes the sensor to become hot so I can't hold it by hand anymore.

 
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The O2 heater is TINY.
The heating element is for the sensing components inside the thimble, not the entire sensor body.
Of course it will eventually make the entire sensor warm....but the guts of the sensor were hot enough to work long before the rest of the sensor burned your fingers.

The typical O2 sensor sensing components have to reach around 600*F before the sensor becomes active.
The PCM will stay in open loop until the primary sensor becomes active...
A working heated O2 sensor can be active in as little as 10-30 seconds after startup.
As soon as the sensor is active, the PCM can enter closed loop





https://en.wikipedia.org/wiki/Oxygen_sensor
The sensor element is a ceramic cylinder plated inside and outside with porous platinum electrodes; the whole assembly is protected by a metal gauze. It operates by measuring the difference in oxygen between the exhaust gas and the external air and generates a voltage or changes its resistance depending on the difference between the two.The sensors only work effectively when heated to approximately 316 °C (600 °F), so most newer lambda probes have heating elements encased in the ceramic that bring the ceramic tip up to temperature quickly. Older probes, without heating elements, would eventually be heated by the exhaust, but there is a time lag between when the engine is started and when the components in the exhaust system come to a thermal equilibrium. The length of time required for the exhaust gases to bring the probe to temperature depends on the temperature of the ambient air and the geometry of the exhaust system. Without a heater, the process may take several minutes. There are pollution problems that are attributed to this slow start-up process, including a similar problem with the working temperature of a catalytic converter.