P2096 2019 Pathfinder

[Stryped]

My wife has a 2019 Pathfinder with 49,000 miles. It runs fine but the check engine light keeps coming on for a bank 1 post cat lean condition. I have tried to attach screen shots of the freeze frame data I have but it won’t upload and says file too large. My guess is it’s the bank 1 sensor 2 oxygen sensor. I have found almost zero info about which side of the engine is bank 1. I know it’s the one with number 1 cylinder but I can’t find that either.
New oxygen sensors either say left side or right side, however not sure if that is from the drivers seat or standing in front of the car. Any help is greatly appreciated!
Also, is there a way to upload these screenshots???

[mdmellott]

The passenger side, right side, is bank 1. O2 sensor 2 will not effect any change in performance of your engine. Think of it as a witness to events that happened upstream. The question is whether or not the witness is lying, therefore defective, or if events upstream are amiss. For example, an exhaust flange leak at the catalytic converter can cause the P2096 fault code. A more thorough diagnosis is needed to determine what has gone wrong.

[Stryped]

It has not affected the performance. But it is a neeer car and I want the check engine light off. The freeze frame data Showed bank 1 sensor 2 at .175 volts, which seemed low to me. Also I can’t hear any exhaust leaks.

That sensor looks hard to get to. How in the world do you get a wrench on it?

Lastly, before starting this, I looked for a Haynes or chilton repair manual but found it isn’t available. Is there another source that is not too expensive?

[Stryped]

Try these freeze frame snap shots:
https://ibb.co/nzjqJtQ
https://ibb.co/x2HkbcY
https://ibb.co/HgDRMqF
https://ibb.co/0yfT4gk
https://ibb.co/txWHj7g
https://ibb.co/3vwRh0r
https://ibb.co/fDxXTGW

[VStar650CL]

On VQ's, P2096 is usually from either an exhaust leak or a bad HO2S (rear O2). However, a bad A/F (front O2) can also cause it. Here's what I'd suggest diagnostically:
1. Scan the A/F sensor voltage while driving steady throttle cruise with a warm engine. Should read around 2.2 volts if the fuel mixture is correct. Above 2.2 volts indicates lean, below indicates rich. If the readings are abnormal then suspect an upstream problem like a vacuum leak or faulty injector. Upstream issues will also show up as abnormal A/F-alpha (STFT).
2. If the A/F reads normal, scan the rear O2 while driving steady throttle cruise with a warm engine. It should read about 1.8V cold and then drop to 0.6-0.8 volts with the cats lit. Compare B1 to B2.
3. If the rear O2 sensor reads low voltage warm, check for exhaust leaks, especially hidden weld cracks.

[mdmellott]

O2B1S2 is low compared to O2B2S2. They should be roughly equal if all else upstream is correct but it doesn't look like it is. The exhaust leak was only an example. What does look off a bit is your bank 1 long term full trim and spark advance. Your IAT is freezing but that's okay assuming you were actually running the engine while the air temperature outside was down around 3deg C.

There is a special O2 sensor wrench socket required to remove and install these sensors but I have doubts the sensor is your problem given the fact that other sensor readings upstream are not quite right.

Haynes and Chilton often lag behind for years before releasing their repair manuals for specific makes and models, if they publish one at all. I wish I could help more but I just don't know what to make of the freeze frame data you have shown, as to what specifically is causing the fault.

[Stryped]

I thought the bank 1 and 2 sensor data looked correct and figured the bank 2 sensor was the culprit.
How do I figure out way is causing this?

[Stryped]

Also temp was cold outside. Freeze frame data was automatically recorded when the code turned back on after being erased.

[mdmellott]

I thought the bank 1 and 2 sensor data looked correct and figured the bank 2 sensor was the culprit.
How do I figure out way is causing this?

The P2096 fault code indicates an issue with bank 1. Bank 2 sensors are not suspect in this case. A good start in how to figure out what is causing this would be to follow the steps VStar650CL outlined above.

Your bank 1 fuel trims are calling for more fuel from injectors 1,3, and 5 than what is being called for by bank 2 injectors 2, 4, and 6, yet the fault code is a lean condition fault which seams backwards unless either an exhaust manifold leak or clogged fuel injectors is creating this condition. The fuel trim is calling for more fuel but that doesn't mean it's delivery more fuel. It's possible that a good fuel system cleaning could make this issue just go away. I always go the easy route first when I think it's possible so my recommendation would be to add a bottle of Chevron Techron Concentrate fuel system cleaner to the fuel tank. There are other fuel system cleaners you can use as well. This is just the one I always use as a maintenance additive at least once a year. I hope this turns out to be just a bit of gunk in the fuel system that can be cleaned out with an additive.

The steps VStar650CL outlined are still your best first steps to start with but adding the fuel system cleaner as well can only help, if it does anything at all.

[Stryped]

Ok. I guess I would just be surprised about a fuel injector being clogged with such low miles and fairly new car.

[Stryped]

Also, what is the easiest way to find a small exhaust leak?

[VStar650CL]

Your bank 1 fuel trims are calling for more fuel from injectors 1,3, and 5 than what is being called for by bank 2 injectors 2, 4, and 6, yet the fault code is a lean condition fault which seams backwards unless either an exhaust manifold leak or clogged fuel injectors is creating this condition. The fuel trim is calling for more fuel but that doesn't mean it's delivery more fuel.

It's not backwards if you think about it in cause-and-effect terms, the ECM pushes STFT higher in order to compensate for a lean mixture. Thus, you get a "lean code" when the ECM runs out of elbow room for enrichment and still sees a lean A/F. That means STFT always indicates the obverse of whichever condition the ECM is trying to correct, it goes higher to correct lean and lower to correct rich.

Ok. I guess I would just be surprised about a fuel injector being clogged with such low miles and fairly new car.

The Pathy from (I think) '17 up is DIG, so it's a bit different from the older VQ35DE. It has the same tendency to carbon-up valves and injectors as any DIG system, especially if it's driven like grandma or gets poor quality fuel. If the problem looks to be upstream, a de-carboning is probably the first thing you should try.

Also, what is the easiest way to find a small exhaust leak?

They sell ultrasonic detectors and you can also use a bunsen torch, but if you own a shop vac, this method is my favorite and doesn't require any burnt thumbs:
https://www.youtube.com/watch?v=l09cp5DBTjk

[mdmellott]

The Pathy from (I think) '17 up is DIG, so it's a bit different from the older VQ35DE. It has the same tendency to carbon-up valves and injectors as any DIG system, especially if it's driven like grandma or gets poor quality fuel. If the problem looks to be upstream, a de-carboning is probably the first thing you should try.

DIG threw me off for a minute. I had to Google it but it still took a bit to search for the meaning. The lightbulb over my head came on when I found GDI. Direct injection engines are notorious for carbon fouled issues, although they are more efficient when well maintained with preventative maintenance. Periodic fuel additives are a must to keep the combustion chamber clean. I can dig it!

[VStar650CL]

Yep, I've seen DIG and GDI used interchangeably for quite some time. The M56 guys in here have been dealing with direct-injection crud for years, here's a lively discussion:

m56-carbon-build-up-t626161.html