Fewer things are simpler than the position of bank 2 sensor 2 on an engine. Yet, as simple as this is, it also remains one of the things that can cause the greatest headaches for vehicle owners, especially those new to using OBD II code readers or those generally new to playing with an engine.
No car owner shouldn’t let this confusion linger, given that there are various avenues to clarify and gain an acute understanding of what this is all about.
Today, I provide such an avenue and offer to simplify the process. I’ll simplify and explain the bank 2 sensor 2 concept to you like you’re in grade school and I hope that at the end of the day, you firmly grasp the concept and take it with you, going forward.
First things first, though: this is the last installment in the series (of bank sensor positions). If you missed the other installments, consider reading them here before proceeding: bank 1 sensor 1, bank 1 sensor 2, and bank 2 sensor 1.
Now, let’s sort out a very important point before proceeding: where does the term ‘bank 2 sensor 2’ apply?
Article Outline
Where Does the Term ‘Bank 2 Sensor 2’ Apply?
The term bank 2 sensor 2 applies when dealing with oxygen (O2) sensors. This term came about based on the bank and position of a particular O2 sensor, relative to the catalytic converter on that bank.
After treating the above, another question that logically applies is what an O2 sensor does. So, what does an O2 sensor do?
What Does an Oxygen (O2) Sensor Do?
It depends: an oxygen sensor is responsible for determining the air-fuel ratios of an ICE by sending data of the content of oxygen it perceives to the ECU for onward ‘treatment’.
An oxygen sensor can also be responsible for the metering the content of oxygen in the gases that leave the catalytic converter and reporting same to the ECU for ‘onward processing’.
What determines which role a catalytic converter plays on any engine bank remains where it is positioned relative to the catalytic converter on that bank.
So, why is more than one catalytic converter needed? Why not just one and we’re done?
Why Is More Than One O2 Sensor Needed?
More than one oxygen sensor is needed because of the nature of tasks needed to be performed both before and after the catalytic converter on each bank.
Since the tasks are radically different, it naturally makes no sense to merge these two functions into one unit, especially since the sensors have to be in different places to efficiently carry out their functions.
So, where is O2 sensor bank 2 sensor 2 located?
Where Is O2 Sensor Bank 2 Sensor 2 Located?
O2 sensor bank 2 sensor 2 is located on the second bank of an engine and is the second sensor on that bank, after the catalytic converter.
Drawing from where bank 2 of a V6 engine is, it is important to remember that bank 2 of a transversely mounted engine (FWDs, mostly) will be on the radiator side of the engine bay.
However, on longitudinally mounted engines (4WDs, AWDs, and RWDs), this is going to be on the passenger side of the vehicle.
So, given its position, is bank 2 sensor 2 upstream or downstream?
Is Bank 2 Sensor 2 Upstream or Downstream?
Bank 2 sensor 2 is a downstream position, specifically on bank 2 of a double-banked engine.
This sensor position is styled this way because it is situated after the catalytic converter and deals primarily with checking the oxygen content of the exhaust, post-catalytic converter ‘processing’.
The other sensor on the same bank, bank 2 sensor 1 is referred to as ‘upstream’ (on that bank) because it is primarily responsible for the air-fuel ratios data it offers the ECU to compute fuel economy in real-time, in a closed loop fashion.
Summary
Bank 2 sensor 2 is the last sensor on the second bank of a double-banked engine and is responsible for checking out the oxygen content of the catalytic converter on that bank.
Knowing what this sensor does, where it is placed, and importantly, how it functions in relation to other sensors and the vehicle’s engine as a whole will enhance a deeper understanding of what needs to be done should any challenge come up and the code reader used to scan the vehicle points out to bank 2 sensor 2.
The above said, even if you’re not interested in sorting out vehicle challenges directly, knowing these details will help you understand your mechanic or technician better when he begins the ‘mechanic speak’ only petrol heads seem to (now) understand.