fastnoypi

The constant 3.30v is just the heater element, just one component for the operation of the o2 sensor. If you still want to prove the operation or failure of the B1S1 sensor, you can bench test it with a propane torch and multimeter.

ssgi4in12

Sorry for giving you much trouble. I have tested the af sensors. When I accelerate rapidly, the voltage drops around 2.80 V or a little and when I decel the voltage jumps to more than 4.0v or more. I will run a test and have a screen shot for your guidance. Could it not be possible that the 02 sensor has gone bad? Because when I accelerate and stay steady at about 2500 rpm the voltage of the 02 sensor bank 1 sensor 2 stays almost on a straight line at 0.1v.

ssgi4in12

This is an update.

Actually, I had to use the actual graphing feature on the Torque Pro to read the live data of the 02 sensor and the af sensor. Pls see the pictures This is the bank 1 sensor 1
This is the bank 1 sensor 2

fastnoypi

not much trouble,....this is what troubleshooting is about. If at steady state 2500rpm your B1S2 is flat and compared to your last oscillating screenshot...i would still guess that the front B1S1 sensor is still bad and giving poor feedback to the ECU. At lower rpms and steady state, the range of the B1S1 to hunt around should be less and the ECU will have to do less adjustments with fueling. That is my conclusion..

You have 3 items that could possibly go bad. Without knowing the age of the sensors, the highest probability component to go bad is the one exposed to the highest heat source B1S1. The most expensive would be the cat, you can eliminate that probability of a faulty cat by heating it up with a long spirited highway drive to burn any unburned oil residue. The least expensive item would be the B1S2 sensor.

You are most welcome to come up with another theory and conclusion on your observations. I hope this helps.

ssgi4in12

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Thanks again. Hopefully with your support I will be able to deal with this cel after all.

When you said : "at steady state 2500rpm your B1S2 is flat and compared to your last oscillating screenshot" are you trying to say that at a steady 2500 rpm that the b1s2 should not remain a steady voltage and should oscillate? That it could be a problem of the Af sensor as well? In the last graphing i sent to you that is at a idle of about 700rpm, you could see that the B1S1 has an oscillation and I have read that it is quite normal. On that graph the b1s2 should be a straight line, right? But it is showing an oscillation too. If you look at the graph of the B1S1, it didn't jump around so much. The minimum was about 3v or so and the highest around 3.5 v or 3.4v.

Can you show me the graphing of your af sensors and the 02 sensor?

ssgi4in12

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This is an update

I took the car on the highway earlier today. I decided to. Graph the B1S1 and B1s2 hoping it would help you diagnose what my problem is. I was driving the car at around the 55MPH and the car was on cruise control.




This graphs above are that of 02 B1S2

02 B1S2 still

The following graph is for Af sensor B1S1

ssgi4in12

fastnoypi, I think I am able to work on my P0420. I bought a cat from a junk yard that was on a 2010 Toyota Camry and replaced the downstream cat.

After the vehicle tests is completed and after driving for more than 100 miles, I think I am able to fix this code. Thank you for your assistance.
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The first tests results that usually fail have consequently passed.

fastnoypi

Sorry i was unable to respond the previous weeks (work trip) but glad you were able to solve your issue by replacing your cat. Could you visibly tell if your original cat was damaged in anyway? Any heavy oil residue in the inlet of the cat?

ssgi4in12

My original cat looked okay except that It had a straight whole that doesn't seem to be covered by the catalyst elements. No heavy oil residue either.

See the picture of the vehicle test below.

I presently get about 12 mpg driving in the city what can I do to improve this? Thanks for your help.