Hi Scotty, I recently checked live data on my 2017 sequoia 5.7.
The O2 sensors bank 1 sensor 1 and bank 2 sensor 2 voltage are showing 3.2 volts
Bank 1 sensor 2 and bank 2 sensor 2 are both around 0.7 volts.
Do I need to replace the sensor 1 on bank 1 and bank 2?
Vehicle is getting worst gas mileage.
There was a code stored P1605 knock control cpu
No check engine light or any other warning lights.
Short term close to zero but long term fuel around +5 or 6%
Also where can I get the O2 sensors apart from the dealership?
On your Toyota the Upstream sensors (bank1 sensor1 and bank2 sensor1) are Air Fuel Ratio sensors.
They should have a voltage of 3.3 volts.
The downstream sensors (Bank1 sensor2 and Bank2 sensor 2) are Oxygen sensors.
They operate in a 0.1 to 0.95 voltage range.
Also, AF sensor and O2 sensor voltages are reversed. With an AF sensor the voltage goes down when rich and it goes up when lean.
With an O2 sensor the voltage goes up when rich and it goes down when lean.
I think your sensors are fine but it looks like your engine is running a little rich
You probably have wideband O2 sensors:
https://www.tirereview.com/troubleshooting-wideband-o2-sensors/
@chucktobias Thank you very much ! I didn't know about the wide band o2 sensors, According to this 3.1 to 3.5 volts is normal so my reading of 3.3 volts should be fine.
Now I can move on to investigate what else is causing the bad fuel consumption
@aliz You're welcome! I've actually never owned a vehicle new enough to be equipped with that type of sensor but do know about them. With a quick search I found that article which gives a very good explanation of how they work.
Those fuel trims don't look too bad, the computer is compensating for a slight lean condition but it shouldn't be a problem. The P1605 code could be significant. It may indicate there is a false knock reading that is causing the computer to retard ignition timing when not really necessary and affecting gas mileage.